Anthropogenic disturbance of the nitrogen (N) cycle has more than doubled the amount of reactive N circulating in the terrestrial biosphere alone. Exchange of reactive/non-reactive nitrogen gases between land and atmosphere are strongly affecting Earth’s atmospheric composition, air quality, climate change and human health. This session seeks to improve our understanding and modelling on how global land use and climate change affect N biogeochemistry in terrestrial and aquatic ecosystems and what atmospheric interactions will be most important in influencing the climate. We seek to link microbiological N cycling processes and exchanges of nitrogen gases at the land-air interface with ecosystem dynamics, air quality and atmospheric chemistry. Despite being intensively studied for a long time, it is still difficult to predicting N transformation pathways because of our lack to quantitatively understand N cycling processes and the numerous processes contributing to (gaseous) N losses in terrestrial ecosystems. The session covers fluxes of different reactive and non-reactive nitrogen gases and the underlying transport and transformation processes in soils and sediments, e.g., fixing of atmospheric dinitrogen (N2) in ecosystems, emission/deposition of ammonia (NH3), nitric oxide (NO), nitrous oxide (N2O), nitrous acid (HONO), nitrogen dioxide (NO2), and N2 (as a result of denitrification) as well as their interactions with ozone (O3), volatile organic compounds (VOCs), free radicals and aerosols in the atmosphere, and the associated impacts on air quality. To predict processes an understanding of the soil heterogeneity is pivotal not only in surface soils and at field scale but also deeper in the soil profile and at small scales (µm). Recent technological improvements of experimental and analytical tools like measurements of N2 fluxes, linking structure and activity of functional microbial communities with flux rates, small scale resolution of soil structure, and improved numerical methods as well as computational power offer new opportunities in this area. Furthermore, the interactions of N cycling with other elemental cycles (e.g., carbon, phosphorus) in ecosystems and terrestrial-aquatic linkages, and feedbacks to biodiversity loss and water pollution will be explored. We welcome contributions covering a wide range of studies including methods development and application of new devices, observational, experimental, and modeling approaches.

The session aims at collecting contributions from all scientists daily faced with the need of discriminating between what is natural and what is the result of the interaction of humans with the surrounding environment, with respect to elemental concentrations. Commonly, geoscientists involved in environmental projects are requested to define local or regional reference concentration values for those chemical substances (mostly potentially harmful elements) and, recently, radioisotopes which can be originating from both geological materials and human driven processes.
To discriminate natural contributions from anthropogenic ones is a very complicated task and several scientists have applied different methods and multiple approaches (from statistics to the weight of evidence) in order to provide guidance and reliable solutions to government institutions and professional stakeholders.
Case studies on solid matrices (soil, sediments, etc.), natural water and other environmental media are of interest for the session together with more methodological studies mostly focusing on the proposal of innovative techniques for defining these values.

The critical zone comprises the Earth's permeable near-surface layer from the top of the canopy to the bottom of the groundwater. It is the zone where hydrosphere, atmosphere, pedosphere and geosphere interact with the biosphere. This fragile skin of our planet, which supports the life and survival of humans maintaining food production and drinking water quality, is endangered by threats such as climate change and land use change.
New approaches and innovative modeling strategies are needed to understand these complex interactions between hydrological, biogeochemical cycles and human resilience processes that may govern critical zone system dynamics, including sources, dynamics and chemistry of water, models to quantify external influences like human activities or erosion, weathering rate, water transfer in the frame of global change and biological feedback mechanisms.
This session focuses on the advancing proxies that may address pressing interdisciplinary scientific questions in coupling various disciplines like hydrology, soil science and biogeochemistry that cover single-site investigations, targeted experiments, remote sensing studies, large data compilations and modelling. This will be illustrated in this session through studies regarding the critical zone as a whole or within its different compartments, including the different environmental processes (geological, physical, chemical, and biological), their couplings and reactive transport modeling , and exploring the cities resilience.

Phosphorus (P) is essential to life, and as a key limiting nutrient, regulates productivity in terrestrial and aquatic systems. Strong geochemical interactions between P and other elements control the mobility and bioavailability of P in the environment, necessitating a coupled understanding of element cycles influencing P. At the same time P provides perhaps the most topical example of a critical resource element whose use is currently inefficiently managed. Leakage of mined P into the environment through a variety of processes (e.g. excess chemical fertiliser usage, or effluent discharges) is responsible for eutrophication and the acceleration of natural P cycling in terrestrial and aquatic systems. This puts P at the forefront of environmental and societal concerns and demands that our biogeochemical knowledge of P cycling ought to be developed through interdisciplinary research. This session aims to explore biogeochemical P cycling in the context of benefitting ‘systems understanding’ spanning terrestrial and aquatic compartments.

Topics included will explore:
Links between P and wider element cycles, for example with other macro- and micro- nutrients and controls of P availability through geochemical parameters such as Fe;
P cycling studies that bring into focus the interplay of biotic and abiotic controls within, and between, environmental compartments;
Drivers of change (climate, management, societal) acting on the coupling of P with other element cycles.
Processes, modelling and management against a background of the key issues for: P release from soil to plants; P release from soil to water; long term P supplies and the global P cycle.
Sustainable use of P, recovering of P from natural and waste water, managing P fluxes in agricultural areas.

Soils represent a major terrestrial carbon store and fulfil a variety of functions from which the environment and humankind benefit. Soils processes operate and interact across the Critical Zone: the near-surface terrestrial layer extending from the bedrock through to the lower atmosphere. Multiple external pressures may result in changes to soil functioning, and we need a good understanding of how soils respond at a range of spatial and temporal scales.

The storage, stability, and cycling of carbon is fundamental to the resilience of soil systems. It is essential that we consider the role of carbon in all soil systems, from the microbial and aggregate scale to the catchment and the whole land surface, in order to better understand the interconnectivity between rocks, soils, plants, and the atmosphere. This is particularly important as soils are facing multiple perturbations, ranging from rapid shifts in land use and management to degradation and long-term environmental and climatic change. To maintain soil functions we need to develop further knowledge of how resistant soils are to these changes, alongside if, and how, they recover.

This session will consider terrestrial carbon pools and dynamics, and explore soil resilience at any, or multiple scales. We welcome contributions that consider processes within and between different elements of the Critical Zone, alongside innovative methods of quantifying and investigating change. Early career researchers are strongly encouraged to apply, and we seek submissions considering empirical, modelling, or meta-analytical approaches.

Rationale: Progressive thawing of permafrost poses a significant threat to the stability of arctic landscapes, and has strong consequences for our climate. To predict the transition of arctic landscapes and its consequence for climate-feedback, we need to understand the dynamics of permafrost thaw. Most climate models assume a gradual, top-down thawing of permafrost, resulting in gradual decomposition of carbon and enhanced plant growth (“Arctic Greening”). However, evidence of an alternative, abrupt thawing trajectory of permafrost (“Arctic Browning”) is currently increasing across the Arctic. Consequences for landscape stability and climate feedback diverge widely between these trajectories, which emphasizes the need to understand their triggers.

Aim: In this session we aim to bring together and integrate the state-of the art on the future development of permafrost ecosystems from various disciplinary backgrounds. Thereby, we hope to improve our understanding of (i) the anticipated occurrence of various thaw phenomena under global warming, (ii) the implications of these various thaw phenomena for permafrost ecosystems and (iii) the implications of various thaw phenomena for climate feedbacks.

We have compiled an exiting programme covering mechanisms, processes and fluxes at different spatial scales, from landscape to microbe. Contributions come from accross all permafrost regions from a wide range of research institutes.

The session will be started of by professor Merritt Turetsky (incoming Director, INSTAAR at the University of Colorado Boulder) on our current knowledge and the main research gaps related to the cross-scale impacts of abrupt thaw phenomena, from local-scale changes that affect water and food security to carbon emissions and global climate. She will also discuss how permafrost thaw is interacting with other disturbance regimes such as wildfire.

A grand challenge facing society in the coming decades is to feed the growing human population in a sustainable and healthy manner. This problem is made more complex by an increasingly globalised food system and its interactions with a changing climate. Agri-food system actors - including policy makers, corporations, farmers, and consumers - must meet this challenge while considering potentially conflicting priorities, such as environmental sustainability (e.g., minimising disturbance to ecosystems via greenhouse gas emissions and the use of water, land, fertilisers and other inputs), economic viability (e.g., revenues for food producers and guaranteed access for consumers), nutritional balance and quality (e.g., addressing overconsumption and undernourishment), and resilience to climate change.
This growing complexity of agri-food systems, which can involve global supply chains and difficult environmental and societal tradeoffs, needs to be better understood.
The type of product (e.g. plant or meat based, fresh or processed), as well as the location and method of production, can play an important role in improving the nutritional quality and environmental sustainability of global food production, to enable healthy and sustainable diets. Quantifying and assessing these multiple outcomes while accounting for the linkages, interconnections, and scales of local and global supply chains will be essential for informing decisions aimed at developing sustainable and resilient agri-food systems.
This session welcomes submissions that quantify and assess a range of outcomes from agri-food systems across multiple spatial and temporal scales, and the trade-offs or synergies between them. The session will include studies providing improved methods for quantifying multiple environmental, economic or social dimensions, studies that incorporate the role of food trade into solution-development, and studies that seek to achieve multiple sustainability goals together.

The interactions between aerosols, climate, and weather are among the large uncertainties of current atmospheric research. Mineral dust is an important natural source of aerosol with significant implications on radiation, cloud microphysics, atmospheric chemistry and the carbon cycle via the fertilization of marine and terrestrial ecosystems.
In addition, properties of dust deposited in sediments and ice cores are important (paleo-)climate indicators.

This interdivision session is open to contributions dealing with:
(1) measurements of all aspects of the dust cycle (emission, transport, deposition, size distribution, particle characteristics) with in situ and remote sensing techniques,
(2) numerical simulations of dust on global and regional scales,
(3) meteorological conditions for dust storms, dust transport and deposition,
(4) interactions of dust with clouds and radiation,
(5) influence of dust on atmospheric chemistry,
(6) fertilization of ecosystems through dust deposition,
(7) any study using dust as a (paleo-)climate indicator including investigations of Loess, ice cores, lake sediments, ocean sediments and dunes.

We especially encourage to submit papers on the integration of different disciplines and/or modeling of past, present and future climates.

(Bio)minerals, in particular carbonates (but also others e.g. phosphates), play an essential role in shaping our understanding of the evolution of life and the Earth System, and constitute one of the most important archives of past climatic and environmental conditions. Geochemical, petrographic or crystallographic approaches have yielded new insights into the physico-chemical conditions governing their formation, including through biomineralisation pathways. These capture vital information about the environment and fluid chemistry during precipitation in the form of their specific elemental or isotopic signatures, mineralogies or micromorphologies. Over the past decades, a refined understanding of both biogenic as well as abiotic carbonates and other mineral archives, together with the development of new analytical methods and palaeo-proxies, has led to numerous breakthroughs in palaeoclimate research. However, the quality and reliability of the climatic and environmental information we extract from these records depends, critically, on careful proxy calibrations and the evaluation of secondary controls such as kinetic or vital effects and diagenetic influences. This session seeks contributions from sedimentology, geochemistry, (palaeo)biology, and mineralogy that utilise carbonate or other relevant (bio)minerals to improve our understanding of past environmental conditions over a broad range of timescales, including (but not limited to) microbialites, mollusc shells, coral skeletons or foraminifera. We welcome experimental or theoretical studies dealing with culturing of calcifying organisms, synthetic mineral precipitation, transformation or alteration processes, elemental partitioning or isotopic fractionation (to give but a few examples). The aim of this session is to synthesize recent progress on the investigation as well as application of these important archives, and to showcase methodological advances that will help us to build a more comprehensive understanding of past global changes.

The session gathers geoscientific aspects such as dynamics, reactions, and environmental/health consequences of radioactive materials that are massively released accidentally (e.g., Chernobyl and Fukushima nuclear power plant accidents, wide fires, etc.) and by other human activities (e.g., nuclear tests).

The radioactive materials are known as polluting materials that are hazardous for human society, but are also ideal markers in understanding dynamics and physical/chemical/biological reactions chains in the environment. Thus, the radioactive contamination problem is multi-disciplinary. In fact, this topic involves regional and global transport and local reactions of radioactive materials through atmosphere, soil and water system, ocean, and organic and ecosystem, and its relation with human and non-human biota. The topic also involves hazard prediction and nowcast technology.

By combining 34 years (> halftime of Cesium 137) monitoring data after the Chernobyl Accident in 1986, 9 years dense measurement data by the most advanced instrumentation after the Fukushima Accident in 2011, and other events, we can improve our knowledgebase on the environmental behavior of radioactive materials and its environmental/biological impact. This should lead to improved monitoring systems in the future including emergency response systems, acute sampling/measurement methodology, and remediation schemes for any future nuclear accidents.

The following specific topics have traditionally been discussed:
(a) Atmospheric Science (emissions, transport, deposition, pollution);
(b) Hydrology (transport in surface and ground water system, soil-water interactions);
(c) Oceanology (transport, bio-system interaction);
(d) Soil System (transport, chemical interaction, transfer to organic system);
(e) Forestry;
(f) Natural Hazards (warning systems, health risk assessments, geophysical variability, countermeasure);
(g) Measurement Techniques (instrumentation, multipoint data measurements);
(h) Ecosystems (migration/decay of radionuclides).

The session consists of updated observations, new theoretical developments including simulations, and improved methods or tools which could improve observation and prediction capabilities during eventual future nuclear emergencies. New evaluations of existing tools, past nuclear contamination events and other data sets also welcome.

Climate change is projected to result in an increase in extreme and compound weather events, which pose a growing threat to human well-being and the achievement of the UN Sustainable Development Goals (SDGs). Further warming is also projected to reduce the efficacy of carbon sinks acting as negative feedbacks on warming and increase the risk of crossing tipping points and triggering cascading changes in the climate and ecosystems. These processes may reduce the Earth system’s resilience, which has the potential to further amplify climate change and extremes and worsen societal impacts.

Maintaining Earth in the Holocene-like conditions that have enabled the development of the world’s societies will require better understanding of feedbacks and tipping dynamics in both the human world and the biophysical Earth. Societies will need to embark on rapid socio-economic and governance transformations in order to both reduce the risk of triggering tipping points and to improve societal resilience to increasingly likely extreme events. Earth resilience brings the complex dynamics and perturbations associated with human activities into Earth system analysis, and increasingly captures socio-economic as well as biophysical dynamics.

In this session we welcome transdisciplinary and cross-scale contributions relating to climate extremes, tipping dynamics, and Earth resilience, covering topics ranging from the cascading impacts of extreme and compound events, key feedbacks and tipping points in both biophysical and human systems, enhancing societal resilience to extreme events, and the potential for rapid social transformations to global sustainability.

Remaining carbon budgets specify the quantity of CO2 that can be emitted before a given warming level (such as the 1.5 °C target) is reached, and are thus of high interest to the public and policymakers. Yet, there are many sources of uncertainty which make it challenging to deduce this finite amount of CO2 emissions. The theoretical foundation of carbon budgets is based on the concept of the Transient Climate Response to cumulative CO2 Emissions (TCRE). This is the pathway-independent ratio of global warming per unit of cumulative CO2 emissions. However, accounting for non-CO2 forcings and changes in albedo or other Earth system feedbacks provides further challenges in calculating TCRE and the remaining carbon budgets.

This session aims to further our understanding of the climate response under different emission scenarios, and to advance our knowledge of associated carbon budgets consistent with meeting various levels of warming. We invite contributions that use a variety of tools, including fully coupled Earth System Models, Integrated Assessment Models, or simple climate model emulators. We welcome studies exploring different aspects related to carbon budgets and the TCRE framework, including: the governing mechanisms behind linearity of TCRE and its limitations, effects of different forcings and feedbacks (e.g. permafrost carbon feedback) and non-CO2 forcings (e.g. aerosols, and other non-CO2 greenhouse gases), estimates of the remaining carbon budget to reach a given temperature target (for example, the 1.5 °C warming level from the Paris Agreement), the role of pathway dependence, the climate-carbon responses to different emission scenarios (e.g. SSP scenarios, or idealized scenarios), and the behaviour of TCRE in response to artificial CO2 removal from the atmosphere (i.e. negative emissions). Contributions from the fields of climate policy and economics focused on applications of carbon budgets are also encouraged.

To showcase their strong thematic connection, the two sessions “Air-Land Interactions (General Session)” and “Understanding and Characterization of Land-Atmosphere Feedback” were merged.

The session is addressed to experimentalists and modellers working on land surface fluxes from local to regional scales. The programme is open to a wide range of new studies in micrometeorology. The topics include the development of new devices, measurement techniques and experimental design methods, as well as novel findings on surface layer theory and parametrization at the local scale. The theoretical parts encompass soil-vegetation-atmosphere transport, internal boundary-layer theories and flux footprint analyses, etc.. Of special interest are comparisons of experimental data, parametrizations and models. This includes energy and trace gas fluxes (inert and reactive) as well as water, carbon dioxide and other GHG fluxes. Specific focus is given to outstanding problems in land surface boundary layer descriptions such as complex terrain, energy balance closure, stable stratification and night time fluxes, as well as to the dynamic interactions with atmosphere, plants (in canopy and above canopy) and soils including the scale problems in atmosphere and soil exchange processes.

The understanding of feedback processes in the land-atmosphere (L-A) system is crucial for advanced modeling and prediction of weather and climate. However, the impact of soil moisture and evapotranspiration on the diurnal cycle of the planetary boundary layer (PBL), clouds, and precipitation remains a sore gap in our understanding of weather processes and climate statistics. For this purpose, the exchange of momentum, water, energy, and carbon at the land surface and at the top of the PBL has to be investigated from the local to regional scales in great detail. In this session, we accept observational and modeling approaches to address these challenges. With respect to the observations, emphasis is put on the application of new sensor synergies for studying L-A exchange processes and entrainment at the PBL top based on long-term data sets or recent field campaigns, e.g., combining multi-tower, scanning lidar, airborne, and satellite observations. With respect to theoretical understanding and modeling, we welcome the study of feedback processes as well as the derivation and application of feedback metrics from the mesoscale to turbulent scales, e.g., derived by large eddy simulations.

The dynamics of the solid Earth and its surface are strongly affected by their interplays as well as biota and climate. These constant feedback systems operate at a variety of spatial and temporal scales that are regulated in a complex system of interactions. For instance, in the critical zone -the terrestrial surface environment ranging from the lower atmosphere to the solid parent material- interplays not only regulate manifold ecosystems and bio-geochemical cycles, but also shape the Earth’s surface at the interface between atmosphere and lithosphere, where soils develop. At much larger scales, plate tectonics and global geodynamics control the physiography, climate and hydrosphere, which in turn strongly affect the surface feedback processes via tectonic, biological, geochemical and hydrological processes. Ultimately, climate and tectonics are prominent macro-ecological drivers of landscape development. But even though the underlying geology and tectonic processes have long been recognized as driving parameters, this is much less so for biological processes. The driving force of microorganisms, plants and animals on the shape of land surfaces is still poorly understood.
Understanding the links between the solid Earth and the external spheres of the Earth has experienced a recent upswing due to advanced analytical techniques, but also thanks to fostered interactions between researchers from different disciplines. This session aims to bring together geoscientists, soil scientists, climatologists and biologists working at different spatial and temporal scales on the feedback interactions between geology, topography, soils, climate and biosphere at the surface of the Earth. The session covers a multitude of topics from the microbial to the geodynamics time and space scales.

Solicited speakers are:
Carina Hoorn, University of Amsterdam, The Netherlands
Alexia Stokes, French National Institute for Agricultural Research – INRA, France
Veerle Vanacker, University of Louvain, Belgium

Stable isotopes and other novel tracers, such as carbonyl sulfide (COS) and clumped isotopes, help to identify and quantify biological, chemical and physical processes that drive Earth's biogeochemical cycling, atmospheric processes and biosphere-atmosphere exchange. Recent developments in analytical measurement techniques now offer the opportunity to investigate these tracers at unprecedented temporal and spatial resolution and precision.

This session includes contributions from field and laboratory experiments, latest instrument developments as well as theoretical and modelling activities that investigate and use the isotope composition of light elements (C, H, O, N) and their compounds as well as other novel tracers for biogeochemical and atmospheric research.

Topics addressed in this session include:
- Stable isotopes in carbon dioxide (CO2), water (H2O), methane (CH4) and nitrous oxide (N2O)
- Novel tracers and biological analogues, such as COS
- Polyisotopocules ("clumped isotopes")
- Intramolecular stable isotope distributions ("isotopomer abundances")
- Analytical, method and modelling developments
- Flux measurements
- Quantification of isotope effects
- Non-mass dependent isotopic fractionation and related isotope anomalies

Public information:
Solicited speaker:
Dr Amaëlle Landais
Laboratoire des sciences du climat et de l’environnement (LSCE)
https://www.lsce.ipsl.fr/Phocea/Pisp/index.php?nom=amaelle.landais

The extraction and analysis of sedimentary ancient DNA (sedaDNA) from Pleistocene and Holocene sediments could potentially revolutionise palaeoecology and biostratigraphy over the next decade. This potential is growing because it has been shown that a) there is preservation of sedaDNA well outside the sub-Arctic and Arctic biomes, b) the costs are reducing, c) the number of laboratories has increased, and most importantly, d) the techniques, such as metabarcoding and shot gun sequencing, are becoming more robust (both in reliability and specificity) and deeper (in taxonomic coverage). At present, and probably for some considerable time to come, sedaDNA will be used alongside microscopic proxies such as pollen, diatoms, foraminifera and insects but it has the potential to be far more specific in characterising local biotic conditions, climatic reconstructions and impact of human activities. This session invites papers using sedaDNA from sediments or soils from any site from lakes to marine deposits and any time period. Methodological papers are also welcome.

Smart Farming is driving a revolution in agriculture, aiming at more productive and sustainable production through precise and resource-efficient decision making, with additional applications in forest and rangeland management. Remotely sensed Big Data from satellite, small unmanned aerial, airborne, in situ and proximal systems, brings both challenges and opportunities which requires high spatial resolution and near real-time mapping capabilities. Success in crop health monitoring, stress identification, soil mapping, fertilizer and irrigation advisories, yield prediction, ecosystem services, and more have been achieved. This session seeks contributions across government, university, private, and nonprofit organizations. It focuses on research methodologies and applications for the use of high spatial resolution or high temporal frequency remotely sensed Big Data for Smart Farming and land management applications. We invite your findings throughout the chain of data collection, storage, transfer, transformation, analytics and discuss how to achieve the goal of more productive and sustainable agriculture production

This multidisciplinary session invites contributions on the use of methods and tools aimed to obtain reliable stable isotope data in various areas. The number of papers using stable isotopes as a tool has increased enormously in the last years. Though this become a very common technique in many science fields (biogeosciences, atmospheric, environment, ecology, forensics, etc), such datasets are difficult to compare / combine as the data quality is often unknown. Different protocols used in different labs, not optimal use of Reference Materials (RMs), isotope fractionation during sample-preparation and within TCEA peripherals, exchangeable hydrogen and oxygen, different data corrections – these are a few examples of potential pitfalls. Evaluating data quality may be especially difficult for novel methodologies such as atmospheric research (e.g. N2O), applications using matrices with exchangeable Hydrogen, CSIA (e.g. fatty acids, amino acids). The session calls for papers that try to search flaws in analytical methods, in comparison of different datasets produced in different labs/methods, creating protocols and tools for QA/QC, investigation of proper RMs to be used for the fit-for-purpose. This session is a plea for high quality stable isotope data to be applied in many sciences and produce data that can be utilized for the future (this is important considering all efforts in OA journals, datasets, etc) including creating large reference datasets as based on data produced by different labs in areas such as biological species, soils, atmospheric observations, forensics. Often such reference datasets should not be used in any case without a proper QC applied.

A remote sensing signal acquired by a sensor system results from electromagnetic radiation (EM) interactions from incoming or emitted EM with atmospheric constituents, vegetation structures and pigments, soil surfaces or water bodies. Vegetation, soil and water bodies are functional interfaces between terrestrial ecosystems and the atmosphere. The physical types of EM used in RS has increased during the years of remote sensing development. Originally, the main focus was on optical remote sensing. Now, thermal, microwave, polarimetric, angular and quite recently also fluorescence have been added to the EM regions under study.
This has led to the definition of an increasing number of bio-geophysical variables in RS. Products include canopy structural variables (e.g. biomass, leaf area index, fAPAR, leaf area density) as well as ecosystem mass flux exchanges dominated by carbon and water exchange. Many other variables are considered as well, like chlorophyll fluorescence, soil moisture content and evapotranspiration. New modelling approaches including models with fully coupled atmosphere, vegetation and soil matrices led to improved interpretations of the spectral and spatio-temporal variability of RS signals including those of atmospheric aerosols and water vapour.
This session solicits for papers presenting methodologies and results leading to the assimilation in biogeoscience and atmospheric models of cited RS variables as well as data measured in situ for RS validation purposes. Contributions should preferably focus on topics related to climate change, food production (and hence food security), nature preservation and hence biodiversity, epidemiology, and atmospheric chemistry and pollution (stratospheric and troposphere ozone, nitrogen oxides, VOC’s, etc). It goes without saying that we also welcome papers focusing on the assimilation of remote sensing and in situ measurements in bio-geophysical and atmospheric models, as well as the RS extraction techniques themselves.
This session aims to bring together scientists developing remote sensing techniques, products and models leading to strategies with a higher (bio-geophysical) impact on the stability and sustainability of the Earth’s ecosystems.

Public information:
BG2.7
Remote Sensing applications in the Biogeosciences

Chairperson: Frank Veroustraete & Willem Verstraeten
10:45
Welcome
1
D530 | EGU2020-5174
10:50
Potential of LiDAR for species richness prediction at Mount Kilimanjaro
Alice Ziegler and the Research Group at the Kilimanjaro
2
D512 | EGU2020-288
10:57
Understanding wetland dynamics using geostatistics of multi-temporal Earth Observation datasets
Manudeo Narayan Singh and Rajiv Sinha
3
D515 | EGU2020-5421
11:04
Twelve years of SIFTER Sun-Induced Fluorescence retrievals from GOME-2 as an independent constraint on photosynthesis across continents and biomes
Maurits L. Kooreman, K. Folkert Boersma, Erik van Schaik, Anteneh G. Mengistu, Olaf N. E. Tuinder, Piet Stammes, Gerbrand Koren, and Wouter Peters
4
D516 | EGU2020-6674
11:11
Evaluation of understory LAI estimation methodologies over forest ecosystem ICOS sites across Europe
Jan-Peter George Jan Pisek and the Tobias Biermann (2), Arnaud Carrara (3), Edoardo Cremonese (4), Matthias Cuntz (5), Silvano Fares (6), Giacomo Gerosa (7), Thomas Grünwald (8) et al.
5
D517 | EGU2020-8263
11:18
Probing the relationship between formaldehyde column concentrations and soil moisture using mixed models and attribution analysis
Susanna Strada, Josep Penuelas, Marcos Fernández Martinez, Iolanda Filella, Ana Maria Yanez-Serrano, Andrea Pozzer, Maite Bauwens, Trissevgeni Stavrakou, and Filippo Giorgi
6
D518 | EGU2020-9071
11:25
Validation of seasonal time series of remote sensing derived LAI for hydrological modelling
Charlotte Wirion, Boud Verbeiren, and Sindy Sterckx
7
D519 | EGU2020-12000
11:32
Potassium estimation of cotton leaves based on hyperspectral reflectance
Adunias dos Santos Teixeira, Marcio Regys Rabelo Oliveira, Luis Clenio Jario Moreira, Francisca Ligia de Castro Machado, Fernando Bezerra Lopes, and Isabel Cristina da Silva Araújo
8
D528 | EGU2020-4418
11:39
Comparison of the Photochemical Reflectance Index and Solar-induced Fluorescence for Estimating Gross Primary Productivity
Qian Zhang and Jinghua Chen
9
D529 | EGU2020-4582
11:46
Weed-crop competition and the effect on spectral reflectance and physiological processes as demonstrated in maize
Inbal Ronay, Shimrit Maman, Jhonathan E. Ephrath, Hanan Eizenberg, and Dan G. Blumberg
10
D531 | EGU2020-6059
11:53
Remote sensing-aid assessment of wetlands in central Malawi
Emmanuel Ogunyomi, Byongjun Hwang, and Adrian Wood
12:00
Open discussion
12:30
End morning session

Chat time: Wednesday, 6 May 2020, 14:00–15:45
Chairperson: Willem Verstraeten Frank Veroustraete
14:00
Welcome back!
1
D534 | EGU2020-10014
14:05
On the surface apparent reflectance exploitation: Entangled Solar Induced Fluorescence emission and aerosol scattering effects at oxygen absorption regions
Neus Sabater, Pekka Kolmonen, Luis Alonso, Jorge Vicent, José Moreno, and Antti Arola
2
D536 | EGU2020-15832
14:12
Evaluating the impact of different spaceborne land cover distributions on isoprene emissions and their trends using the MEGAN model.
Beata Opacka, Jean-François Müller, Jenny Stavrakou, Maite Bauwens, and Alex B. Guenther
3
D537 | EGU2020-10633
14:19
Application of Copernicus Global Land Service vegetation parameters and ESA soil moisture data to analyze changes in vegetation with respect to the CORINE database
Hajnalka Breuer and Amanda Imola Szabó
4
D538 | EGU2020-13332
14:26
How valuable are citizen science data for a space-borne crop growth monitoring? – The reliability of self-appraisals
Sina C. Truckenbrodt, Friederike Klan, Erik Borg, Klaus-Dieter Missling, and Christiane C. Schmullius
5
D539 | EGU2020-18493
14:33
Learning main drivers of crop dynamics and production in Europe
Anna Mateo Sanchis, Maria Piles, Julia Amorós López, Jordi Muñoz Marí, and Gustau Camps Valls
6
D540 | EGU2020-19003
14:40
Modelling understory light availability in a heterogeneous landscape using drone-derived structural parameters and a 3D radiative transfer model
Dominic Fawcett, Jonathan Bennie, and Karen Anderson
7
D543 | EGU2020-5151
14:47
Global assimilation of ocean-color data of phytoplankton functional types: Impact of different datasets
Lars Nerger, Himansu Pradhan, Christoph Völker, Svetlana Losa, and Astrid Bracher
8
D544 | EGU2020-5251
14:53
PROSPECT-PRO: a leaf radiative transfer model for estimation of leaf protein content and carbon-based constituents
Jean-Baptiste Féret, Katja Berger, Florian de Boissieu, and Zbyněk Malenovský
9
D547 | EGU2020-13447
15:00
Inverting a comprehensive crop model in parsimonious data context using Sentinel 2 images and yield map to infer soil water storage capacity.
André Chanzy and Karen Lammoglia
10
D550 | EGU2020-18798
15:07
Study on The Extraction Method and Spatial-temporal Characteristics of Irrigated Land in Zhangjiakou City
Zijuan Zhu, Lijun Zuo, Zengxiang Zhang, Xiaoli Zhao, Feifei Sun, and TianShi Pan
11
D551 | EGU2020-19953
15:14
Remote sensing and GIS based ecological modelling of potential red deer habitats in the test site region DEMMIN (TERENO)
Amelie McKenna, Alfred Schultz, Erik Borg, Matthias Neumann, and Jan-Peter Mund
15:21
Open discussion
15:45
End afternoon session

This session is open to all contributions in biogeochemistry and ecology where stable isotope techniques are used as analytical tools, with a focus on stable isotopes of light elements (C, H, O, N, S, ...). We welcome studies from both terrestrial and aquatic (including marine) environments as well as methodological and experimental, theoretical and modeling studies that introduce new approaches or techniques (including natural abundance work, labeling studies, multi-isotope approaches, clumped and metal isotopes).

Assessing and mitigating the environmental impacts of solid waste is critical to develop sustainable waste management strategies. Solid waste deposits from the extractive industry, i.e. extractive waste (EW), and municipal solid waste (MSW) landfills can be an environmental threat through groundwater or surface water contamination in addition to the human health risks they might pose. Furthermore, MSW landfills account for 5% of the anthropogenic methane production worldwide.
In line with Europe’s Circular Economy Action Plan, several strategies emerged aiming for sustainability regarding the use of natural resources, a responsible consumption/production, dynamic landfill management (DLM) and, mainly for EW, the recovery/reuse of waste produced during exploitation and processing activities. These include the reduction of emissions through control of microbial activity, sustainable mining and recovery of raw materials and energy, the rehabilitation of the occupied land among others. Yet, the controlling mechanisms of microbial activity and other degrading processes in waste are largely unknown, and traditional methods based on the analysis of samples generally lack the required resolution for an adequate characterization of biogeochemical processes. Hence, there is a big demand of innovative techniques for the characterization and monitoring of EW and MSW disposal sites. In particular, reliable information about the composition and geometry of waste depositions, as well as about their biogeochemical status is needed. Geophysical methods are well suited to fulfill these requirements as they can provide real-time information about subsurface physical properties in a non-invasive way and with high resolution in space and time.
The main topics to be discussed in this session deal with the use of innovative methods, including, but not limited to, geophysical approaches for:
- Characterization and monitoring of MSW and of EW from quarries and mines.
- Case studies for the detection and assessment of environmental pollution associated to the disposal of solid waste.
- Evaluation of the risks associated with the management of waste and integrated approaches towards sustainable mining,
- Innovative technologies to exploit EW facilities and to improve the systematic recovery of waste flows. Case studies related to the recovery of EW from quarrying and mining activities, including valorization as construction materials.

In an urbanizing world with major land-use changes, both human (social and economic) and natural systems and their environmental challenges and constraints need to be considered in order to achieve sustainable urban development. Nature‐based solutions (NBS) in urban areas can make anthropogenic landscapes more ecosystem-compatible, enhancing ecosystem services, preserving biodiversity, mitigating land degradation, and increasing urban resilience to environmental changes. Maintaining and restoring ecosystems and green–blue areas within urban regions is important for a) increasing the well‐being of urban populations, b) providing multifunctional services, such as storm water mitigation and local climate regulation, c) improving energy efficiency of buildings, and d) mitigating carbon emissions. Implementing NBS in urban areas is of growing importance worldwide, and particularly in the EU political agenda, as a way to attain some of the Sustainable Development Goals (e.g. Sustainable cities and communities), and to reinforce the New Urban Agenda. Implementing efficient NBS in urban landscapes requires integrated and interdisciplinary approaches.

This session aims to enhance the scientific basis for sustainable urban development and resilience and advance knowledge of innovative nature-based approaches to face environmental changes (e.g. in land use and climate) and simultaneously provide better understanding of associated social-ecological interactions. This session seeks to:

• Better understanding of advantages and disadvantages of NBS in Urban environments;
• New methods and tools to investigate the role of NBS in the context of environmental change, in particular the effectiveness of NBS in enhancing urban resilience;
• New insights and perspectives of NBS, particularly their role in providing urban ecosystem services, such as storm water regulation and reducing greenhouse gas emissions;
• Identifying opportunities for and barriers to implement NBS, driven by current regulatory frameworks and management practices - and how the former can be reaped and the latter overcome;
• Presenting overviews and case studies of NBS projects that also involve the private sector and market-based mechanisms;
• Interactions between NBS and the Sustainable Development Goals (SDGs);
• Approaches for integrating actors involved in landscape design and urban planning.

Human interaction with the environment has gone through several stages of evolution. Being a product of the natural evolution of living organisms in the biosphere, Homo sapiens as a species has evolved in the geochemical conditions of the virgin biosphere. The rapid development of intellectual abilities of this genus allowed, first, to survive in adverse environmental conditions around the whole world, then, to cultivate the land, transform the entire system of biocenoses, and now to create a new habitat for man exclusively. The result was a significant geochemical transformation of the virgin biosphere, but a kind of punishment for the achieved progress was the emergence of a number of endemic diseases of a geochemical nature. Nowadays a variety of anthropogenic sources of pollution and their location in various natural geochemical conditions require not only constant monitoring of the chemical state of soil, water, air and food products, but also the development of spatially differentiated approaches to assessing the risk of provoked diseases. To solve this problem it is necessary concertedly interpreting a geochemical and medical information in order to assess the risks to human health associated with modern natural and anthropogenic geochemical features in urban and rural habitats. During session we propose to discuss:
1) global trends of health transformation in new geochemical environment of modern noosphere;
2) criteria for determining pollution level depending on environmental and geochemical constrains;
3) new approaches to assess the risk of diseases of geochemical nature in different countries;
4) the problem of mapping the risk zones, related to negative medical effects due to deficiency or excess of certain chemical elements or compounds.
Session co-sponsored by the European Association of Geochemistry.

There are many ways in which machine learning promises to provide insight into the Earth System, and this area of research is developing at a breathtaking pace. If unsupervised, supervised as well as reinforcement learning can hold this promise remains an open question, particularly for predictions. Machine learning could help extract information from numerous Earth System data, such as satellite observations, as well as improve model fidelity through novel parameterisations or speed-ups. This session invites submissions spanning modelling and observational approaches towards providing an overview of the state-of-the-art of the application of these novel methods.

Accurate and precise atmospheric measurements of greenhouse gas (GHG) concentrations reveal the rapid and unceasing rise of global GHG concentrations due to human activity. The resulting increases in global temperatures, sea-level, glacial retreat, and other negative impacts are clear. In response to this evidence, nations, states, and cities, private enterprises and individuals have been accelerating GHG reduction efforts while meeting the needs of global development. The urgency, complexity and economic implications of GHG reductions demand strategic investment in science-based information for planning and tracking emission reduction policies and actions. In response, the World Meteorological Organization (WMO) Global Atmosphere Watch Program (GAW) and its partners have initiated the development of an Integrated Global Greenhouse Gas Information System (IG3IS). IG3IS combines atmospheric GHG concentration measurements and human-activity data in an inverse modeling framework to help decision-makers take better-informed action to reduce emissions of greenhouse gases and pollutants that reduce air quality. This service is based on existing and successful measurement and analysis methods and use-cases for which the scientific and technical skill is proven or emerging.

This session intends to gather presentations from researchers and decision-makers (user-community) on the development, implementation and use of atmospheric measurement-based “top-down” and data-driven “bottom-up” GHG emission inventory estimates, and the combination of both approaches, explicit in space and time, to deliver actionable emissions information at scales where human activity occurs and emission reduction is most effective. This session will also showcase the new projects and efforts to develop “good-practice” standards under the World Meteorological Organization (WMO) Integrated Global Greenhouse Gas Information System (IG3IS), which is part of WMO’s commitment to science-based services.

Remote sensing techniques are widely used to monitor the relationship between the water cycle and vegetation dynamics and its impact on the carbon and energy cycles. Measurements of vegetation water content, transpiration and water stress contribute to a better global understanding of the water movement in the soil-plant system. This is critical for the detection and monitoring of droughts and their impact on biomass, productivity and feedback on water, carbon and energy cycles. With the number of applications and (planned) missions increasing, this session aims to bring researchers together to discuss the current state and novel findings in the remote observation of the interactions between vegetation and hydrology. We aim to (1) discuss novel research and findings, (2) exchange views on what should be done to push the field forward, and (3) identify current major challenges.

We encourage authors to submit presentations on:
• Remote sensing data analyses,
• Modelling studies,
• New hypothesis,
• Enlightening opinions.

During the passage of precipitation through the soil-plant-atmosphere interface, water and solutes are redistributed by the plant canopy and subsurface flow and transport processes. Many of these dynamic interactions between vegetation and soil are not yet well understood. This session brings together the vibrant community addressing a better understanding of ecohydrological processes taking place between the canopy and the root zone. Innovative methods investigating throughfall, stemflow, hydraulic redistribution, and root water uptake in various environments shed light on how water and solutes are routed in the thin layer covering the terrestrial ecosystems. The session further covers open questions and new opportunities within the ecohydrological community regarding methodological developments such as the analysis of stable isotope, soil moisture, throughfall or solute dynamics.
Invited Speakers:
Christiane Werner, University of Freiburg, Germany
Alexandra Ponette-González, University of North Texas, USA

Methane is an important greenhouse gas that has contributed ∼25% of the radiative forcing experienced to date. Despite methane’s short atmospheric lifetime (~10 years), global methane concentrations have grown more than three times faster than carbon dioxide since the industrial revolution. This makes methane emission mitigation an effective way to reduce the short-term rate of warming. In contrast to carbon dioxide, anthropogenic methane emissions originate from a large variety and number of diffuse point sources that are mostly independent of combustion processes. As a result, systematic atmospheric measurements are needed to inform emission inventories and mitigation strategies.

This session will highlight research that focuses on methane emissions from human activities (e.g., fossil fuel infrastructure, fire, rice production, ruminants, landfills and waste). Particular emphasis is on studies collecting atmospheric observations at different spatio-temporal scales with the aim to (1) reduce the uncertainty in the measured magnitude of emissions, (2) identify source-specific emission patterns and mitigation opportunities, and (3) inform stakeholders, such as regulators and industry representatives, on mitigation pathways.

Mercury (Hg) is a toxic global pollutant of great environmental concern. The UNEP Minamata convention on mercury, a legally-binding international treaty aiming to reduce negative impacts of Hg on the environment, has entered into force in 2017. Anthropogenic activities have altered the global Hg cycle to a great extent and many ecosystems are threatened by exposure to elevated levels of Hg and its different species. For instance, neurotoxic and bioaccumulating methyl-Hg is formed under the influence of anaerobic microorganisms in a variety of natural systems but the controls on this key process are still far from being understood. Further active Hg research areas include exchange processes at the atmosphere-soil-plant interface and their importance for understanding atmospheric Hg deposition, the behavior and long-term fate of Hg at contaminated sites, as well as global cycling models assessing the evolution of historic Hg fluxes from different natural and anthropogenic sources. In the past few years, a number of novel research tools based on microbiological, spectroscopic, isotopic, and modelling techniques have been developed to improve our understanding of Hg cycling in the environment. This session presents new contributions on present-day Hg cycling in the environment using field-based, experimental, and/or modelling approaches on local to global scales, as well as contributions focusing on long- and short-term reconstruction of Hg as a pollutant over time using natural archives such as ice-cores, tree-rings, lake sediments and peat bogs. We particularly welcome research addressing the effects of the implementation of the Minamata convention on mercury levels in the environment and new approaches to assess its effectiveness.

The development and functions of ecosystems and their responses to environmental drivers are inherently long-term processes that need to be studied along gradients in time and space. Global anthropogenic drivers of change interact with natural processes, causing uncertainties, tipping points and potential crises in system behaviour. Further, most ecosystem services are strongly interlinked and require a multi- and transdisciplinary approach that allows for the simultaneous analysis of multiple processes and feedbacks. The environmental drivers affecting one domain are also easily reflected in other domains. Considering the current extensive land use changes and climate change, integrated studies where aquatic and terrestrial ecosystems are studied in combination are urgently required. The sites and platforms of the long-term ecosystem, critical zone and socio-ecological research networks and research infrastructures (ILTER, eLTER) distributed around the globe offer a unique tool for this, while coupled ecosystem-scale experimentation (AQUACOSM) can further strengthen the hypothesis testing.

This session focuses on research performed at sites and platforms implementing a whole system approach, also cross the terrestrial and aquatic domains. Emphasis will be on results presenting long-term changes and responses of ecosystem and socio-ecological processes to environmental drivers, as well as ecosystem-scale experiments (mesocosms) and observations scaling up from sites to larger regions up to the continental level.

We welcome studies linking biodiversity loss, climate change, and other anthropogenic pressures to ecosystems. We encourage contributions using interdisciplinary and multidisciplinary approaches, addressing relationships among different ecosystem compartments (vegetation, soils, waters etc.) or between ecological and social systems, as well as transdisciplinary studies that incorporate diverse forms of knowledge beyond the scientific community.

This session is linked to the Pan-Eurasian EXperiment (PEEX; www.atm.helsinki.fi/peex), a multi-disciplinary, -scale and -component climate change, air quality, environment and research infrastructure and capacity building programme. It is aimed at resolving major uncertainties in Earth system science and global sustainability issues concerning the Arctic, Northern Eurasia and China regions. This session aims to bring together researchers interested in (i) understanding environmental changes effecting in pristine and industrialized Pan-Eurasian environments (system understanding); (ii) determining relevant environmental, climatic, and other processes in Arctic-boreal regions (process understanding); (iii) the further development of the long-term, continuous and comprehensive ground-based, air/seaborne research infrastructures together with satellite data (observation component); (iv) to develop new datasets and archives of the continuous, comprehensive data flows in a joint manner (data component); (v) to implement validated and harmonized data products in models of appropriate spatio-temporal scales and topical focus (modeling component); (vi) to evaluate impact on society though assessment, scenarios, services, innovations and new technologies (society component).
List of topics:
• Ground-based and satellite observations and datasets for atmospheric composition in Northern Eurasia and China
• Impacts on environment, ecosystems, human health due to atmospheric transport, dispersion, deposition and chemical transformations of air pollutants in Arctic-boreal regions
• New approaches and methods on measurements and modelling in Arctic conditions;
• Improvements in natural and anthropogenic emission inventories for Arctic-boreal regions
• Physical, chemical and biological processes in a northern context
• Aerosol formation-growth, aerosol-cloud-climate interactions, radiative forcing, feedbacks in Arctic, Siberia, China;
• Short lived pollutants and climate forcers, permafrost, forest fires effects
• Carbon dioxide and methane, ecosystem carbon cycle
• Socio-economical changes in Northern Eurasia and China regions.
PEEX session is co-organized with the Digital Belt and Road Program (DBAR), abstracts welcome on topics:
• Big Earth Data approaches on facilitating synergy between DBAR activities & PEEX multi-disciplinary regime
• Understanding and remote connection of last decades changes of environment over High Asia and Arctic regions, both land and ocean.

Earth Systems Models aim at describing the full water- and energy cycles, i.e. from the deep ocean or groundwater across the sea or land surface to the top of the atmosphere. The objective of the session is to create a valuable opportunity for interdisciplinary exchange of ideas and experiences among members of the Earth System modeling community and especially atmospheric-hydrological modelers.
Contributions are invited dealing with approaches how to capture the complex fluxes and interactions between surface water, groundwater, land surface processes, oceans and regional climate. This includes the development and application of one-way or fully-coupled hydrometeorological prediction systems for e.g. floods, droughts and water resources at various scales. We are interested in model systems that make use of innovative upscaling and downscaling schemes for predictions across various spatial- and temporal scales. Contributions on novel one-way and fully-coupled modeling systems and combined dynamical-statistical approaches are encouraged. A particular focus of the session is on weakly and strongly coupled data assimilation across the different compartments of the Earth system for the improved prediction of states and fluxes of water and energy. Merging of different observation types and observations at different length scales is addressed as well as different data assimilation approaches for the atmosphere-land system, the land surface-subsurface system and the atmosphere-ocean system. The value of different measurement types for the predictions of states and fluxes, and the additional value of measurements to update states across compartments is of high interest to the session. We also encourage contributions on use of field experiments and testbeds equipped with complex sensors and measurement systems allowing compartment-crossing and multi-variable validation of Earth System Models.

Since the launch of the first Earth Resources Technology Satellite 1 in 1972, land imaging technology has evolved rapidly and transformed science research innovation. The U.S. Geological Survey (USGS) is partnering with U.S. Federal agencies, incorporating input from state/local, academic, industry, and international communities, to document current usage and benefits, and improvement needs for future land imaging observation data and products. The European Commission in collaboration with the European Space Agency is also engaged in a continuous collection of user needs to drive the implementation of its programme. This includes feedback from users but also considering emerging needs from changes in society, policies and technologies.

These activities promote a needs-driven, prioritized investment decision process for land imaging systems, products, and services to better serve the broad land imaging community. This session will provide an overview of the current landscape of land imaging capabilities, applications, user needs for future systems, and the future landscape of land imaging including the rapidly expanding commercial sector.

This session will highlight activities within U.S. Federal agencies, academic, state/local, and international communities, and within the European Union institutions, agencies, including the European Space Agency and EU Member States.
We also invite submissions showcasing new and emerging multi-disciplinary land imaging applications, technology trends, and future needs and opportunities.

Terrestrial (semi-)natural and managed ecosystems like forests, grasslands, croplands and wetlands are important sources and/or sinks for greenhouse gases (GHGs: CO2, CH4, N2O) as well as for other trace gases (VOCs, NH3, NO, HONO, Rn, He, etc.). Soils sustain complex patterns of life and act as biogeochemical reactors. Production and consumption of gases and their transport in the soil result in typical patterns of gas concentrations that play a fundamental role affecting many soil functions, such as root and plant growth, microbial activity, and stabilization of soil organic carbon. Plants can contribute to ecosystem exchange by uptake and transport of soil-produced gases to the atmosphere, in-situ production and consumption of gases in plant tissues, and alternation of carbon- and nitrogen-turn-over in adjacent soil. However, the contribution of these individual processes to the net ecosystem GHGs exchange is still unclear and seems to depend on many aspects as plant/tree species, ecosystem type, soil type and conditions, environmental parameters and seasonal dynamics.
Due to the simultaneous influence of various environmental drivers and in case of managed land also management activities, the flux patterns in soil-plant-atmosphere systems are often complex and difficult to attribute to individual drivers. However, it is clear that Interactions between soil, vegetation and the atmosphere exert a crucial role controlling the global budget of these gases and need to be well understood to make any predictions for future.
The session addresses experimentalists and modellers working on trace gas fluxes and their dynamics, production and consumption processes, transport mechanisms and interactions in terrestrial ecosystems at any relevant scale, and from the full climatic and hydrological ecosystem range. We welcome also contributions presenting methodological aspects, development and application of new devices and methods, and modelling studies that seek to integrate our understanding of trace gas exchange in terrestrial ecosystems.

Public information:
EGU this year is different than it used to be. We will be able to use the “Sharing Geoscience Online” platform to present and exchange about our research data and results.
But EGU is not only sharing scientific content, but it is also meeting people. We always had session dinners in our session, where people could meet, have a drink, and exchange ideas about science and life in general.

We want to continue this tradition.
We will have a “Session-Dinner”-at-home online on Thursday, May 7, 19:00 (Vienna Time)

If you are interested in joinnig us, you are welcome - please let me know, and I ll share the link:

Martin.Maier@bodenkunde.uni-freiburg.de

Kind regards

Martin

From pole to pole, peatlands contain up to 30% of the world’s soil carbon pool, illustrating their important role in regulating the global carbon cycle. Currently, peatlands are under various pressures such as a changing climate or nutrient loading with unknown consequences for their functioning as carbon sinks and stores, including the uptake or release of the greenhouse gases carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O).

However, it is not clear how the carbon reservoir will react to these pressures and how vulnerable or resilient these ecosystems are. Tipping points, thresholds, and system state changes are often referred to in the literature, but how much do we really know about these in a peatland context? This session will focus on the observed or predicted changes on the biogeochemistry of natural peatlands, caused by external pressures such as climate change, fire or nutrient loading.

We invite studies concentrating, for example, on the effects of climate change, nutrient loading or fire on GHG or nutrient dynamics, peatland vegetation, atmosphere-biosphere interactions or carbon stock changes. Field observations, experimental, and modelling studies of both high- and low-latitude peatlands are welcomed.

Plant traits extend the range of earth observations to the level of individual organisms, providing a link to ecosystem function and modeling in the context of rapid global changes. However, overcoming the differences in temporal and spatial scales between plant trait data and biogeochemical cycles remains a challenge.

This session will address the role of plant species traits, biodiversity, acclimation, and adaptation in the biogeochemical cycles of water, carbon, nitrogen, and phosphorus. We welcome conceptual, observational, experimental and modeling approaches, and studies from the local to the global scale, including in-situ or remote sensing observations.

Shorter return period of climate and hydrological extremes has been observed in the changing climate, which affects the distribution and vitality of ecosystems. In many regions, available water is a crucial point of survival. Risk can be enhanced by the exposure and/or by the vulnerability of the affected ecosystem as well as by land use/land cover change.
The session should provide a multidisciplinary platform for sharing experiences and discussing results of local and catchment scale case studies from a wider range of relevant fields such as
• observed impacts and damage chains in natural and agricultural ecosystems induced by droughts and intense rainfall events;
• correlation between the underlying environmental factors (e.g. climate, water storage capacity of soil) and the distribution/vitality of ecosystems;
• integrated application or comparison of databases and methods for the identification and complex assessment of ecosystem responses to abiotic stress factors;
• expected tendencies of abiotic risk factors affecting and limiting the survival of the vulnerable species.
Contributions are encouraged from international experiences, ongoing research activities as well as national, regional and local initiatives.

Observations and simulations of the terrestrial carbon and water budget are fundamental to understanding biosphere-atmosphere interactions under a changing climate. A wide range of processes, covering various spatial and temporal scales, influence the response of terrestrial carbon fluxes (NEE, GPP, TER, fires, methane, lateral export) to changes in land and atmospheric moisture availability. The vegetation and soils also contribute to regulating land-atmosphere moisture fluxes (evapotranspiration, precipitation), which in turn feeds back to the water cycle and the climate system. Observations or modeling assumptions made at different spatial and temporal resolutions also pose new challenges in terms of scaling and uncertainty quantification.

This session aims to synthesize our current understanding and identify knowledge gaps and transferability across scales, We encourage contributions exploring carbon-water interactions from multiple perspectives (remote-sensing, experimental, modelling) and covering all types of biomes (boreal, temperate and tropical forests, grasslands, wetlands, …). Contributions might include for example: 1) disentangling the impact of co-varying drought-driven changes to soil moisture, vapour pressure deficit, or temperature on land carbon fluxes, 2) using in-situ or satellite observations to evaluate or improve the representation of water-carbon interactions and biological processes in models, 3) developing and implementing new representations of plant and ecosystem responses to land and atmospheric moisture stress (e.g. through plant hydraulics, optimality approaches, etc.) and 4) scaling carbon- water interactions from the leaf-level to the global scale and bridging the gap between data streams taken at different temporal and spatial scales (e.g. using modeling, theoretical or statistical approaches).

Solicited speaker: Alexandra Konings, Stanford University

Public information:
Observations and simulations of the terrestrial carbon and water budget are fundamental to understanding biosphere-atmosphere interactions under a changing climate. A wide range of processes, covering various spatial and temporal scales, influence the response of terrestrial carbon fluxes (NEE, GPP, TER, fires, methane, lateral export) to changes in land and atmospheric moisture availability. The vegetation and soils also contribute to regulating land-atmosphere moisture fluxes (evapotranspiration, precipitation), which in turn feeds back to the water cycle and the climate system. Observations or modeling assumptions made at different spatial and temporal resolutions also pose new challenges in terms of scaling and uncertainty quantification.

This session aims to synthesize our current understanding and identify knowledge gaps and transferability across scales, We encourage contributions exploring carbon-water interactions from multiple perspectives (remote-sensing, experimental, modelling) and covering all types of biomes (boreal, temperate and tropical forests, grasslands, wetlands, …). Contributions might include for example: 1) disentangling the impact of co-varying drought-driven changes to soil moisture, vapour pressure deficit, or temperature on land carbon fluxes, 2) using in-situ or satellite observations to evaluate or improve the representation of water-carbon interactions and biological processes in models, 3) developing and implementing new representations of plant and ecosystem responses to land and atmospheric moisture stress (e.g. through plant hydraulics, optimality approaches, etc.) and 4) scaling carbon- water interactions from the leaf-level to the global scale and bridging the gap between data streams taken at different temporal and spatial scales (e.g. using modeling, theoretical or statistical approaches).

Solicited speaker: Alexandra Konings, Stanford University

In this session we focus on GHG emissions and an understanding of how management activities and different land use combinations modify the GHG exchanges of different landscape mosaics. A particular emphasis will be placed on how to parcel different management practices and land uses together to provide an optimum configuration that minimizes GHG emissions. We also welcome contributions that report on the GHG mitigation potential of different management practices or land uses. Given the potential role of forests in GHG offsetting this session also seeks to bring together scientists working on the exchange of CO2, CH4 and N2O in forest ecosystems. We also welcome contributions from conventional flux measurements on cropland, grazing systems, and forests, as well as innovative approaches for gas sampling and small scale/on-farm micrometeorological measurements, together with satellite and modelling studies that seek to integrate our understanding of landscape GHG exchanges. We further invite contributions that aim at combining measurements with modelling approaches, and/or those that are trying to disentangle how management practices modify the processes responsible for GHG production and consumption at the farm or ecosystem level. This session also will benefit from contributions from FACCE ERA-GAS programme.

Public information:
This session is focused on land use mosaics and greenhouse gas emissions.

We have a varied programme, including methane uptake by forest soils, re-wetting effects on nitrous oxide emissions, solar panel forests and hedgerow carbon sequestration, so there is something for everyone!

I would encourage you to look at the abstracts and presentations for this session so that we can have an informed and lively discussion.

Please join us on Thursday 7 May, from 1400-15.45

Bruce Osborne

The assessment of forest vulnerability and resilience in the sight of global ecological, social and economic changes is a relevant issue. In recent decades, forest vulnerability is rapidly increasing worldwide and forecasting changes in tree health is becoming a challenge. Forest dieback episodes have been recorded in all biomes affecting different tree and shrub species. These dieback cases are revealing the high vulnerability of some species, particularly conifers, manifested as a loss in tree vigour, growth decline and sometimes tree death. Tree mortality commonly involves multiple, interacting factors, ranging from drought to insect pests and diseases, often making the determination of a single cause unrealistic. The need of understanding and predicting changes in tree mortality, growth and recruitment in response to dieback is essential to improve vegetation and C cycle models.
There is a common agreement on the key role of interdisciplinary research and the combined use of complementary tools to improve the monitoring and projection of forest vulnerability and dieback.
This session focuses on efforts to improve our understanding on: i) causes and mechanisms related to forest vulnerability and dieback; ii) potential changes in tree species composition, forest structure and extent of dieback under current and future climate change scenarios; iii) evaluation of which functional anatomical and hydraulic traits make some tree species or stands and tree populations more prone to environmental-induced dieback and decline IV) assessment of the role and interaction of insect disease and other abiotic factors on mortality; V) possible contribution of novel methods and approaches in quantitative wood anatomy to evaluate plant adaptive capability and identify early-stress indicators; VI) how trees die from drought and how to quantitatively assess tree mortality rates and the magnitude of tree mortality episodes associated to climate change events.
Contributions will focus on an integrated multi-scale (from cells to plant communities, ecosystems and global approaches), multi-temporal (from tree-ring series analysis to xylogenesis and long-term forecasting) and interdisciplinary (microscopy and individual plant physiology to remote sensing) frameworks.

Land use and land cover change (LULCC), including land management, has the capacity to alter the climate by disrupting land-atmosphere fluxes of carbon, water and energy. Thus, there is a particular interest in understanding the role of LULCC as it relates to climate mitigation and adaptation strategies. Much attention has been devoted to the biogeochemical impacts of LULCC, yet there is an increasing awareness that the biogeophysical mechanisms (e.g. changes in surface properties such as albedo, roughness and evapotranspiration) should also be considered in climate change assessments of LULCC impacts on weather and climate. However, characterizing biogeophysical land-climate interactions remains challenging due to their complexity. If a cooling or a warming signal emerges depends on which of the biogeophysical processes dominates and on the size and pattern of the LULCC perturbation. Recent advances exploiting Earth system modelling and Earth observation tools are opening new possibilities to better describe LULCC and its effects at multiple temporal and spatial scales. This session invites studies that improve our general understanding of climate perturbations connected to LULCC from both biogeophysical and biogeochemical standpoints, and particularly those focusing on their intersection. This includes studies focusing on LULCC that can inform land-based climate mitigation and adaptation policies. Both observation-based and model-based analyses at local to global scales are welcome.

Carbon allocation is a key process in ecosystems: it is coupled with plant growth, fuels metabolism and plays a crucial role for carbon sequestration in standing biomass and soil organic matter. While the importance of carbon allocation for plant and ecosystem functioning and the carbon balance is widely recognized, we still lack a comprehensive understanding of the underlying mechanisms, responses to global changes and wider biogeochemical implications. Open questions include: 1) what drives carbon allocation in plants and ecosystems?; 2) what is the fate of newly assimilated carbon?; 3) what determines the allocation of nonstructural carbon to growth, metabolism and storage?, 4) how does carbon allocation affect nutrient and water relations in plants and ecosystems?; and 5) how do allocation patterns change under changing environmental conditions and what are the consequences for biogeochemical cycles? This session invites contributions from observational, experimental and modelling studies.

The need to predict ecosystem responses to anthropogenic change, including but not limited to changes in climate and increased atmospheric CO2 concentrations, is more pressing than ever. Global change is inherently multi-factorial and as the terrestrial biosphere moves into states without a present climate analogue, mechanistic understanding of ecosystem processes and their linkages with ecosystem function is vital to enable predictive capacity in our forecast tools.

This PICO session aims to bring together scientists interested in advancing our fundamental understanding of vegetation and whole-ecosystem processes. We are interested in contributions focused on advancing process- and hypothesis-driven understanding of plant ecophysiology, biodiversity and ecosystem function. We welcome studies on a range of scales from greenhouse and mesocosm experiments to large field manipulative experiments and process-based modelling. We encourage contributions of novel ideas and hypotheses in particular those from early stage researchers and hope the session can create an environment where such ideas can be discussed freely.

The terrestrial vegetation carbon balance is controlled not just by photosynthesis, but by respiration, carbon allocation, turnover (comprising litterfall, background mortality and disturbances) and wider vegetation dynamics. Observed, and likely future, changes in vegetation structure and functioning are the result of interactions of these processes with atmospheric carbon dioxide concentration, climate and human activities. The quantification and assessment of such changes has proven extremely challenging because of a lack of observations at large scales and over the long time periods required to evaluate trends.

Thus, our current understanding of the environmental controls on vegetation dynamics and properties, and, in turn, their impact on carbon stocks in biomass and soils, is limited. The behaviour of vegetation models regarding many of the processes mentioned above remains under-constrained at scales from landscape to global. This gives rise to high uncertainty as to whether the terrestrial vegetation will continue to act as a carbon sink under future environmental changes, or whether increases in autotrophic respiration or carbon turnover might counteract this negative feedback to climate change. For instance, accelerated background tree mortality or more frequent and more severe disturbance events (e.g. drought, fire, insect outbreaks) might turn vegetation into carbon sources. Likewise, understanding how these shifts in dynamics will influence forest composition is crucial for long-term carbon cycle projections.

Uncertainties and/or data gaps in large-scale empirical products of vegetation dynamics, carbon fluxes and stocks may be overcome by extensive collections of field data and new satellite retrievals of forest biomass and other vegetation properties. Such novel datasets may be used to evaluate, develop and parametrize global vegetation models and hence to constrain present and future simulations of vegetation dynamics. Where no observations exist, exploratory modelling can investigate realistic responses and identify necessary measurements. We welcome contributions that make use of observational approaches, vegetation models, or model-data integration techniques to advance understanding of the effects of environmental change on vegetation dynamics, tree mortality and carbon stocks and fluxes at local, regional or global scales and/or at long time scales.

This session explores the potentials and limitations of various remote sensing applications in forestry, with the focus on the identification and integration of different methodologies and techniques from different sensors and in-situ data for providing qualitative and quantities forest information.
In general, remote sensing allows examining and gathering information about an object or a place from a distance, using a wide range of sensors and platforms. A key development in remote sensing has been the increased availability of data with very high temporal, spatial and spectral resolution. In the last decades, several types of remote sensing data, including optical, multispectral, radar, LiDAR from terrestrial, UAV, aerial and satellite platforms, have been used to detect, classify, evaluate and measure the earth surface, including different vegetation cover and forest structure. For the forest sector, such information allows efficient quantification of the state and monitoring of changes over time and space, in support of sustainable forest management, forest and carbon inventory or for monitoring forest health and their disturbances. Remote sensing data can provide both qualitative and quantitative information about forest ecosystems. In a qualitative analysis, forest cover types and species composition can be classified, whereas the quantitative analysis can measure and estimate different forest structure parameters related to single trees (e.g. DBH, height, basal area, timber volume, etc.) and to the whole stand (e.g. number of trees per unite area, spatial distribution, etc.). However, to meet the various information requirements, different data sources should be adopted according to the application, the level of detail required and the extension of the area under study. The integration of in-situ measurements with satellite/airborne/UAV imagery, Structure from Motion, LiDAR and geo-information systems offers new possibilities, especially for interpretation, mapping and measuring of forest parameters and will be a challenge for future research and application.

Fire is an essential feature of terrestrial ecosystems and an important component of the Earth system. Climate, vegetation characteristics, and human activity regulate fire occurrence and spread, but fires also feedback to them in multiple ways. The mechanisms of interactions between fire, land, atmosphere, and society are complicated and remain poorly understood quantitatively. This session welcomes contributions on all aspects of links between fire, biosphere, climate, and humans to share recent advances and foster interdisciplinary discussions. We encourage all abstracts that explore the role of fire in the Earth system at any temporal and spatial scale using modeling, field and laboratory observations, and/or remote sensing, with an emphasis on studies that advance our understanding on (1) impacts of fire on weather, climate, and atmospheric chemistry, (2) interactions between fire, biogeochemical cycles, land water and energy budgets, and vegetation composition and structure, (3) influence of humans on fire and vice versa (e.g., impact of fire on air and water quality, human health, and economy), (4) fire characteristics (e.g. fire duration, emission factor, emission height, smoke transport), (5) spatial and temporal changes of fires in the past, present, and future, (6) fire products and models, and their validation and error/bias assessment, and (7) analytical tools designed to enhance situational awareness among fire practitioners and early warning systems, addressing specific needs of operational fire behavior modeling.

Sustainable agriculture is needed to ensure that both present and future societies will be food secure. Current agricultural productivity is already challenged by several factors, such as climate change, availability and accessibility of water and other inputs, socio-economic conditions, and changing and increased demand for agricultural products. Agriculture is also expected to contribute to climate change mitigation, to minimize pollution of the environment, and to preserve biodiversity.
Assessing all these requires studying alternative land management at local to global scales and to assess agricultural production systems rather than individual products.
This session will focus on the modeling of agricultural systems under global change, addressing challenges in adaptation to and mitigation of climate change, sustainable intensification and environmental impacts of agricultural production. We welcome contributions on methods and data, assessments of climate impacts and adaptation options, environmental impacts, GHG mitigation and economic evaluations.

Monitoring and modeling of vegetation and ecosystem dynamics is fundamental in diagnosing and forecasting Earth system states and feedbacks. However, the underlying ecosystem processes are still relatively poorly described by Earth system models. Confronting terrestrial biogeochemical models at multiple temporal and spatial scales with an ever-increasing amount and diversity of Earth observation data is therefore needed.

To this end, the rapidly growing amount of satellite data has fostered the development of novel global Earth observation products of vegetation and ecosystem properties (such as sun-induced fluorescence SIF, microwave vegetation optical depth VOD, biomass, spectral plant traits, fuel moisture content, multi-sensor climate data records, new high-resolution products), which complement more traditional products like NDVI, LAI or fAPAR. In this session, we present the most recent advances in:

(1) the production of global land surface biophysical and biochemical variables from satellite observations;

(2) assessment of plausibility, validation and inter-comparisons of these products;

(3) their use in the development of data-driven models to estimate and analyze ecosystem processes;

(4) their use in studying global ecosystem dynamics related to climate variability and change;

(5) benchmarking and improvement of global vegetation models through statistical analysis and model-data integration techniques.


The latter may consider methodological foci or include applications related to the monitoring and modeling of terrestrial vegetation and ecosystem dynamics for timescales from days to decades, also including multiple data streams.

Globally, 10–20% of peatlands have been drained for agriculture or forestry emitting close to 5% of global anthropogenic CO2 emissions. Some European countries report more than 60% of their emissions from agriculture and land use, land use change and forestry (LULUCF) originating from drained organic soils, and the fate of South-East Asian peatlands is of global concern. Most peatland-rich countries address peatlands poorly in national emission reporting and climate change mitigation strategies.

Peatland restoration for conservation purposes can solve many problems related to drained peatlands and has been implemented for decades now. However, innovative mitigation measures that sustain economically viable biomass production while reducing negative environmental impacts including greenhouse gas (GHG) emissions, fire risk and supporting ecosystem services of organic soils are only currently studied. Management measures include, but are not limited to, productive use of wet peatlands, improved water management in conventional agriculture and innovative approaches in conservation-focused rewetting projects. Production systems with high water tables can generate food, feed, fiber, fuel and raw materials for chemical industry. A better understanding of ecosystem functioning and underlying processes is the basis for sustainable use of wet landscapes. Implementing these innovations in practice and integrating them into national GHG inventories remains a challenge.

We invite studies addressing all types of peatland management, i.e. agriculture, forestry and “classical” restoration, as well as their integration into GHG inventories. Work on all spatial scales from laboratory to national level addressing biogeochemical and biological aspects and experimental and modelling studies are welcome. Especially research on development of systems with details on commodities with viable value chains and income generation are of interest. Furthermore, we invite contributions addressing policy coherence and identifying policy instruments for initiating and implementing new management practices on organic soils.

This session is organized as a joined effort of Global Research Alliance “Peatland Management” working group, Greifswald Mire Centre, Thünen Institute and the WETSCAPES project (ESF/14-BM-A55-xxx/16) funded by the European Social Fund and the Ministry of Education, Science and Culture of Mecklenburg-Western Pomerania.

Human activities are altering a range of environmental conditions, including atmospheric CO2 concentration, climate, and nutrient inputs. However, understanding and predicting their combined impacts on ecosystem structure and functioning and biogeochemical cycles is challenging. Divergent future projections of terrestrial ecosystem models reveal uncertainties about fundamental processes and missing observational constraints. Models are routinely tested and calibrated against data from ecosystem flux measurements, remote sensing, atmospheric inversions and ecosystem inventories. These model projections constrain the current mean state of the terrestrial biosphere, but they provide limited information on the sensitivity of ecophysiological, biogeochemical, and hydrological processes to environmental changes. Observational and ecosystem manipulation studies (e.g., Free-Air Carbon Dioxide Enrichment (FACE), nutrient addition or warming experiments) can complement modelling studies with unique insights and inform model development and evaluation. This session focuses on how ecosystem processes respond to changes in CO2 concentration, warming, altered precipitation patterns, water and nutrient availability. It aims at fostering the interaction between the experimental and modelling communities by advancing the use of observational and experimental data for model evaluation and calibration. We encourage contributions from syntheses of multiple experiments, model intercomparisons and evaluations against ecosystem manipulation experiments, pre-experimental modelling, or the use of observations from "natural experiments". Contributions may span a range of scales and scopes, including plant ecophysiology, soil organic matter dynamics, soil microbial activity, nutrient cycling, plant-soil interactions, or ecosystem dynamics.

Mountain forests significantly contribute to the habitability of mountain regions, reducing risk for people, infrastructure and resources suffering from natural hazards, including floods, debris floods, debris flows, snow avalanches and rockfalls. Mountain forests are, however, also highly sensitive to climate variability, potentially eroding their protection function under climate change. Since the 19th century, European and other countries in mountain regions have developed a variety of forest and landscape managing techniques for sustaining the protective function of forests. Those management techniques can be seen as are part of the European natural and technical heritage and are of high public interest. Yet, natural disturbances, changes in forest structure and biodiversity, and regeneration failure might pose substantial challenges to forest and landscape management. We thus need to increase our understanding of how the protective function of mountain forests is affected by climate change. The aim of the session consequently is to compile current knowledge on climate change impacts on mountain forests ecosystems and their protective function against natural hazards across the globe.
Potential topics might include the monitoring and modelling of changing disturbance regimes and their impacts on the protective functions of forests, regeneration and recovery failure of mountain forests, and the effects of human land use and changing societal demands on mountain forests and their protective forests. We hope to gain a broad overview on global mountain forest ecosystems in the context of protection against natural hazards.

Soil organic matter (SOM) dynamics play a major role in determining soil fertility, atmospheric CO2 concentrations and climate change adaptation. However, the relationship between soil C persitance and vulnerability under increasing atmospheric temperature and growing global population is poorly understood. Therefore better constraints on SOM pools and fluxes and their reaction to global change are required allowing to disentangle soil C persistence and vulnerability. This session focuses on empirical and modeling studies of soil carbon and its response to warming, and ecosystem vulnerability in different soil types. Contributions focusing on organic as well as mineral soils in contrasting climatic regions are welcome. They may include interdisciplinary research from experiments and observation networks collecting long term, geographically distributed data. International efforts working towards soil data harmonization and data-model sharing are also featured.

Climate changes can alter ecosystem processes and functioning, however these changes are difficult to predict due to multiple interactions and feedbacks between different processes and components within the system. Studies on single processes, e.g. at the soil, root or plant scale, can shed light into individual responses but are limited in their power to be up-scaled to the ecosystem level. Stable isotopes or other tracers can be used to scale information on processes on the soil, rhizosphere, vegetation and atmosphere exchange to the ecosystem level. Using natural or experimentally induced ecosystem responses to climate change drivers when combined with stable isotope labelling or other novel techniques can provide a critical link to elucidate interlinked responses to disturbances. This session invites contributions from studies that investigate ecosystem responses from the molecular and microbial to atmospheric scale, using novel techniques such as compound or position-specific stable isotope labelling. We welcome studies from experimental, as well as natural ecosystems.
Invited speaker: Dan Yakir

Ecosystem management in forests, croplands, grassland, mires, rangelands amongst others is a major driver of net greenhouse gas (GHG) exchange between an ecosystem and the atmosphere. Within this session we aim at better understanding on how management activities in terrestrial ecosystems modify the exchange of the three major GHGs: carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). We are particularly interested in in-situ measurements (both short and long-term) of either a single GHG, or studies that jointly assess all three GHGs from managed ecosystems. Direct comparison studies of different managements or managed vs. unmanaged systems are encouraged. We further invite contributions that aim at combining GHG measurements with modeling approaches, and/or those that try to disentangle how management practices modify the processes responsible for GHG production/consumption at the plant, soil or ecosystem level. As an output if this session we anticipate, (1) learning about individual approaches currently being used to better understand the effects of management activities on GHG budgets, and (2) to compile information and develop standardized guidelines for existing and future studies allowing for direct comparison across systems.

Over 600 flux stations are presently operational as part of continental and national flux networks and under the umbrella of the FLUXNET global network, with multiple dozens more flux stations operating as smaller dedicated networks and standalone projects. A total of over 2100 flux tower locations had provided data in the past covering large portions of the globe.

In the last 10 years, multiple new highly advanced software, codes and routines to analyze various aspects of this wealth of flux and ancillary data were developed by individuals, research groups, regional and national networks. From raw-data processing over multi-method data cleaning, gap filling and flux partitioning to flux-footprint budgeting and bottom-up modeling, such advanced tools offer an unprecedented analytical power to the ecosystem flux community.

This session is designed to bring together scientists and developers who have developed such tools utilizing the latest in flux methodology, ecosystem measurements, new instrumentations, and modern computing, so as to provide an orientation map of available tools to ecosystem researchers, flux scientists and ecosystem modelers.

If you developed a tool or code that you think is useful for understanding ecosystem processes and that facilitates data processing, this is the right session to submit to.

Tropical ecosystems play an important role in the regional and global climate system through the exchange of greenhouse gases (GHGs), water and energy and provide important ecosystems services. However, increasing pressures from rapidly growing populations have resulted in intensive transformation of tropical landscapes resulting in deforestation, agricultural expansion, erosion and fire. Carbon-rich ecosystems such as peatlands and forests are particularly threatened, as deforestation and drainage alter their fluxes of dissolved organic carbon (DOC), carbon dioxide and methane. Across the tropics, land use impacts, in combination with climate change, are altering biogeochemical cycles and hydrology, highlighting the need for new observations and understanding that will support sustainable management in these ecosystems.

However, we are limited by both a lack of data and fundamental understanding of tropical landscapes and peatlands. In this session we welcome contributions that provide insights on how changes in climate and land use impact biogeochemical cycles and ecohydrology in the tropics. We invite work on pristine, degraded and agricultural ecosystems, including but not limited to forests, savannahs, oil palm plantations, peatlands, wetlands, lakes and rivers. At the site-level, we welcome studies including laboratory and field experiments, eddy covariance and flux measurements and process-based models. At larger spatial scales, we invite the application of earth observation and modeling tools including airborne and remote sensing products (i.e. LIDAR, SAR and Optical), forest mapping, calibration and validation of new tools, and large-scale simulations, including those addressing climate sensitivity, fire risk and disturbance. Finally, we encourage representation of all tropical regions, including South and Southeast Asia, Africa and the Americas.

Natural disturbances are a primary driver of forest dynamics, thus shaping their composition and structure, and determining succession trajectories.
With the multitude of functions and services simultaneously and increasingly required from forest ecosystems, it is crucial to improve our understanding of the impact of natural disturbances on forests, also in light of the potential alterations introduced by different global change drivers, mostly due to anthropogenic activities. Unprecedented disturbances, both in type and intensity, due to changes in disturbance regimes are occurring in many parts of the world.
Further attention is required to the many ways in which multiple disturbances (of biotic, abiotic and anthropogenic origin) interact with each other, thereby modifying the likelihood of occurrence and the effects of one another.
Despite an increasing awareness of the fundamental ecological role of natural disturbances, forest management still requires solid scientific input on how to increase the resistance and resilience of forests, and manage naturally disturbed landscapes to promote forest regeneration.
This complex situation calls for multi-scale, multi temporal, and multidisciplinary studies, taking advantage of field (in-situ) and remote sensing approaches, in order to capture the large heterogeneity and variability of the patterns and processes involved. In this session, we invite contributions from all fields in order to promote knowledge on disturbance ecology, to implement monitoring of forest recovery, and to promote sustainable forest management.

The world has been significantly transformed by human actions at least throughout the course of the Holocene with implications for ecological functioning, climate regulation, etc. Central to furthering understanding of the timing, extent and impact of these transformations is quantification of vegetation cover and land-use at local, regional and continental scales, and at centennial to millennial timescales. Recent accelerations in the intensity of human land use have been implicated for changes in biodiversity, however, relationships between land use change and diversity are complex and include important historical legacies. This session explores recent developments in, and applications of, the quantification of land-cover and land-use from palaeobotanical and palynological data in globally diverse landscapes. We welcome all contributions on methodological advances, and applications to historic and prehistoric long-term dynamics and drivers of land-use, anthropogenic land-cover and land-system change, as well as shifts in biodiversity patterns. These contributions may include pollen and other palaeobotanical approaches to land-use and land-cover change, archaeological and historical records and related palaeoecological data (e.g. palaeoentomological data), as well as modelling studies on anthropogenic land-cover change (ALCC) and climate-land use interactions.

This session contributes to the PAGES LandCover6k working group (http://pastglobalchanges.org/landcover6k). The primary goal of LandCover6k is to use global empirical data on past land-use and anthropogenic land-cover change to evaluate and improve Anthropogenic Land-Cover Change scenarios for earth system modellers (e.g. the World Climate Research Programme CMIP and PMIP initiatives). However, submissions do not need to be explicitly linked to this working group and we welcome abstracts with wider reaching themes spanning environmental responses to human activities, such as biodiversity loss and changes in ecosystem functioning.

Gross photosynthetic CO2 uptake is the single largest component of the global carbon cycle and a crucial variable for monitoring and understanding global biogeochemical cycles and fundamental ecosystem services. Nowadays routine measurements of the net biosphere-atmosphere CO2 exchange are conducted at the ecosystem scale in a large variety of ecosystem types across the globe. Gross photosynthetic and ecosystem respiratory fluxes are then typically inferred from the net CO2 exchange and used for benchmarking of terrestrial biosphere models or as backbones for upscaling exercises. Uncertainty in the responses of photosynthesis and respiration to the climate and environmental conditions is a major source of uncertainty in predictions of ecosystem-atmosphere feedbacks under climate change. On the other hand transpiration estimates both at ecosystem to global scales are highly uncertain with estimates ranging from 20 to 90 % of total evapotranspiration. The most important bottleneck to narrow down the uncertainty in transpiration estimates is the fact that direct measurements of transpiration are uncertain and techniques like eddy covariance measure only the total evapotranspiration.
During the last decade, technological developments in field spectroscopy, near surface remote sensing, including sun-induced fluorescence, isotope flux measurements and quantum cascade lasers have enabled alternative approaches for constraining ecosystem-scale photosynthesis, respiration and transpiration. On the other hand a variety of approaches have been developed to directly assess the gross fluxes of CO2 and transpiration by using both process based and empirical models, and machine learning techniques.
In this session we aim at reviewing recent progress made with novel approaches of constraining ecosystem gross photosynthesis, respiration and transpiration and at discussing their weaknesses and future steps required to reduce the uncertainty of present-day estimates. To this end we are seeking contributions that use emerging constrains to improve the ability to quantify respiration and photosynthesis processes, transpiration and water use efficiency, at scales from leaf to ecosystem and global. Particularly welcome are studies reporting advancements and new developments in CO2 and evapotranspiration flux partitioning from eddy covariance data, the use of carbonyl sulfide, stable isotopes approaches, and sun-induced fluorescence.

Urban greenspaces play a prime role in making city liable and natural. They are a vital part of the city on the way to achieve sustainable development. They have great values in offering ecosystem services, improving environmental quality and maintaining biodiversity. Smart allocation of greenspaces in the cities will optimize their values to enhance the adaptive capacity in the context of the climate change and anthropogenic processes. Due to competition for space in the urban region, the urban forests and urban greenspaces are vulnerable to the encroachments associated with the growth of the city and the damages linking to extreme weather.

This session aims to gather original viewpoints and bring up discussions concerning various opportunities and challenges in different areas of science of earth observations, environmental health in association with vegetation health, economy and industrialization, in particular, liking to urban greenspaces. innovative techniques and approaches are encouraged to be introduced to foster applications of remote sensing and GIS in contemporary practice. Urban greenspaces are expected to be assessed, monitored and managed by the means of remote sensing and GIS technologies and benchmark models. It is also encouraged to present and discuss the green indices, conceptual frameworks, implemented approaches, models and innovative techniques to make city smarter in greening. Outcomes of the comprehensive studies are essential to make the cities more adaptive in the context of climate change.

The rhizosphere is regarded as the soil compartment with the highest level of nutrient flux through a multitude of interactions between plants, soil, and (micro)biota. Roots and associated (micro)organisms interact with heterogeneous soil environments that provide habitats for biota on various scales. High metabolic activity and nutrient cycling can be observed from single root tips to whole root systems which makes the rhizosphere of central importance for ecosystem functioning.
The main knowledge-gaps in rhizosphere research are related to the difficulty in mechanistically linking the physical, chemical and biological processes, taking place at different scales (nm to cm) in the rhizosphere and to the challenge of upscaling these processes to the scale of the root system and the soil profile. The key for overcoming these knowledge gaps is to understand rates of matter flux, and to link the spatial arrangement of the different interconnected components of the rhizosphere with their temporal dynamics. This requires concerted efforts to combine methods from different disciplines like plant genomics, imaging, soil physics, chemistry and microbiology.
We welcome experimental and modelling studies on rhizosphere functioning that aim at revealing spatial gradients of e.g. functional biodiversity of microorganisms, uptake and release patterns by roots, soil structure modification by root growth (and vice versa) as well as feedbacks between those processes in order to improve our mechanistic understanding of emerging properties like water acquisition, nutrient cycling, plant health, soil structure development and feedbacks among them.

Viticulture is one of the most important agricultural sectors of Europe with an average annual production of 168 million hectoliters (54% of global consumption). The concept of “Terroir” links the quality and typicity of wine to the territory, and, in particular, to specific environmental characteristics that affect the plant response (e.g. climate, geology, pedology). The environmental factors that drive the terroir effect vary in space and time, as well as soil and crop management.
Understanding the spatial variability of some environmental factors (e.g. soil) is very important to manage and preserve terroirs and face the current and future issue of climate change. In this sense, it is important to stress that in the last decade, the study of terroir has shifted from a largely descriptive regional science to a more applied, technical research field, including: sensors for mapping and monitoring environmental variables, remote sensing and drones for crop monitoring, forecast models, use of microelements and isotopes for wine traceability, metagenome approach to study the biogeochemical cycles of nutrients.
Moreover, public awareness for ecosystem functioning has led to more quantitative approaches in evidencing the relations between management and the ecosystem services of vineyard agroecosystems. Agroecology approaches in vineyard, like the use of cover crops, straw mulching, and organic amendments, are developing to improve biodiversity, organic matter, soil water and nutrient retention, preservation from soil erosion.
On those bases, the session will address the several aspects of viticultural terroirs:
1) quantifying and spatial modelling of terroir components that influence plant growth, fruit composition and quality, mostly examining climate-soil-water relationships; 2) terroir concept resilience to climate change; 3) wine traceability and zoning based on microelements and isotopes; 4) interaction between vineyard management practices and effects on soil and water quality as well as biodiversity and related ecosystem services.

Soil organic matter (SOM) is well known to exert a great influence on physical, chemical, and biological soil properties, thus playing a very important role in agronomic production and environmental quality. Globally SOM represents the largest terrestrial organic C stock, which can have significant impacts on atmospheric CO2 concentrations and thus on climate. The changes in soil organic C content are the result of the balance of inputs and losses, which strongly depends on the processes of organic C stabilization and protection from decomposition in the soil. This session will provide a forum for discussion of recent studies on the stabilization and sequestration mechanisms of organic C in soils, covering any physical, chemical, and biological aspects related to the selective preservation and formation of recalcitrant organic compounds, occlusion by macro and microaggregation, and chemical interaction with soil mineral particles and metal ions.

The MacGyver session focuses on novel sensors made, or data sources unlocked, by scientists. All geoscientists are invited to present
- new sensor systems, using technologies in novel or unintended ways
- new data storage or transmission solutions sending data from the field with LoRa, WIFI, GSM, or any other nifty approach
- started initiatives (e.g., Open-Sensing.org) that facilitate the creation and sharing of novel sensors, data acquisition and transmission systems.

Connected a sensor for iPhone to an Arduino or Raspberri Pi? 3D printed an automated water quality sampler? Or build a Cloud Storage system from Open Source Components? Show it! New methods in hydrology, plant physiology, seismology, remote sensing, ecology, etc. are all welcome. Bring prototypes and demonstrations to make this the most exciting Poster Only (!) session of the General Assembly.

This session is co-sponsered by MOXXI, the working group on novel observational methods of the IAHS.

Documenting the diversity of human responses and adaptations to climate, landscapes, ecosystems, natural disasters and the changing natural resources availability in different regions of our planet, cross-disciplinary studies in human-landscape interaction provide valuable opportunities to learn from the past. This session is targeted at providing a platform for scientists with common interests in geomorphology and geoarchaeology and, in particular, the complex and integrated nature of the relationship between landforms, geomorphological processes and societies during the Anthropocene, and how this has developed over time at different spatial and temporal scales.

This session seeks related interdisciplinary papers and specific geomorphological or geoarchaeological case-studies that deploy various approaches and tools to address the reconstruction of former and present human-environmental interactions from the Palaeolithic period through the modern. Topics related to records of the Anthropocene from Earth and archaeological science perspectives are welcome. We are inviting contributions that focus on the two-way interactions between geomorphological processes/landforms and human activity. These should show how the various factors of the physical environment interact with the Anthroposphere, and, in turn, how population and individuals may affect (and change) these factors. Furthermore, contributions may include (but are not limited to) insights about how people have coped with environmental disasters or abrupt changes; defining sustainability thresholds for farming or resource exploitation; distinguishing the baseline natural and human contributions to environmental changes. In this context, topics of different fields may be addressed in the session such as landform evolution, landscape sensitivity and resilience in the overall context of the interrelation between geomorphology and society, geohazards, geoheritage and conservation, geomorphological responses to (and evidence for) environmental change, and applied geomorphology. Moreover, issues of scale and hierarchies may be addressed, and methods and applications of dynamic rather than equilibrium ideas and metaphors. Ultimately, we would like to understand how strategies of human resilience and innovation can inform our modern strategies for addressing the challenges of the emerging Anthropocene, a time frame dominated by human modulation of surface geomorphological processes and hydroclimate.

Fate and activity of heavy metals, pesticides, PAHs and other xenobiotics depend on their interaction with humic substances present in soil, coal, freshwater and marine systems. They may be deactivated due to various interactions with humic substances, and from the other hand, xenobiotics may affect the properties of humic substances. These processes are dependent on the properties of specific fractions, including humic acids, fulvic acids and humin. Papers covering various aspects of mutual interaction between humic substances and heavy metals, pesticides and PAHs are welcome. This will provide deeper insights and understanding of the mechanisms of xenobiotics sorption on humic substances, as well as their influence on properties of humic substances occurring in terrestrial and aquatic systems.

Peatlands develop in specific hydrological settings and react sensitively to changes in climatic and hydrological boundary conditions. The hydrology of peatlands is fundamental to their function and development. Soil hydrological properties can change drastically after human interventions such as drainage, causing challenges for both model parameterisation and re-wetting measures. Pristine peatlands offer and regulate a number of ecosystem services such as biodiversity, carbon storage and nutrient retention. Hydrology is a key control for a number of these services but studies on peatland hydrology are surprisingly scarce. Furthermore, the effects of peatlands (both pristine and disturbed) on flood retention and on regional climate are much debated, but there seem to be more myths than data. As hydrological and biotic processes in peatlands are strongly coupled, estimating the eco-hydrological response of peatlands under climate change and linking it to vegetation development and greenhouse gas emissions is a demanding task for modellers.
This session aims to bring together peatland scientists to focus on improved understanding of hydrological processes operating in all types of peatlands. Peatlands being considered may be pristine or disturbed and degraded and may also include rehabilitation and re-wetting interventions. Hydrological data may have been collected for other reasons (e.g. carbon flux calculations) but the session welcomes re-examination of such hydrological data in its own right or as supporting data for other studies. All aspects of peatland hydrology are welcome to boost knowledge transfer across scales and methods; from the pore to the global scale, including laboratory, field, remote sensing and modelling studies on hydrological, hydrochemical or geophysical topics, as well as ecosystem service assessments.

Soil is the largest carbon (C) reservoir in terrestrial ecosystems with twice the amount of atmospheric C and three times the amount in terrestrial vegetation. Carbon related ecosystem services include retention of water and nutrients, promoting soil fertility and productivity and soil resistance to erosion. In addition, changes in the soil C can have strong implications for greenhouse gas emissions from soil with implications in environmental health.

Drivers controlling C pools and its dynamics are multiple (e.g. land use/vegetation cover, climate, texture and bedrock, topography, soil microbial community, soil erosion rates, soil and other environment management practices, etc. ) and some of them are mutually interacting. Also, rate of net soil C loss can be high in some environments due to both climatic constrains or management. Thus, investigation of C dynamics should be addressed with regards to the climate change and climatic extreme events to provide a better understanding of carbon stabilization processes and thus support decision making in soil management and climate adaptation strategies.

The present session highlights the importance of soil C changes, and the interaction among the mechanisms affecting C concentration and stocks in soil. Discussion about the proxies to measure and model C stocks, with special emphasis to cropping systems and natural/semi-natural areas, is encouraged. These proxies should be approached at varying the availability of soil and environment information, including, e.g., soil texture, rainfall, temperature, bulk density, land use and land management, or proximal and remote sensing properties. Studies presented in this session can aim to a wealth of aims, including soil fertility, provision of ecosystem services, and their changes, and the implication for economy, policy, and decision making.

Types of contribution appreciated include, but are not limited to, definitive and intermediate results; project outcomes; proposal of methods or sampling and modelling strategies, and the assessment of their effectiveness; projection of previous results at the light of climate change and climatic extremes; literature surveys, reviews, and meta-analysis. These works will be evaluated at the light of the organisation of a special issue in an impacted journal

Organo-mineral associations are recognized as key factors in stabilizing organic matter within microaggregates and even larger structural units in soil. A better understanding of the mechanisms behind the formation and stabilization are essential to predict or manage soil
structure, fertility and organic matter dynamics. Recent studies point to the highly dynamic nature
of the structural units of soil, while the major interaction mechanisms, e.g. adsorption and
and coprecipitation, are strongly dependent on the environmental conditions. Microaggregates including the OM-associations may form, alter, and break up depending on the local milieu (i.e., the presence of minerals, redox conditions, pH, water content, type of organic molecules, biotic drivers, etc.), under natural and management-induced variations in soil. With the growing experimental and observational evidence of the existence and build-up of these sub-micrometer soil compounds, in turn the number of modeling approaches increase that aim for an advanced mechanistic understanding of the formation and stabilization processes, the resulting 3d-structures, and their role in the functioning of soil. With this session, we respond to the growing awareness and intensive debate of the importance of the sub-micrometer-architecture for the dynamics and functioning of soils. Presentations will focus on studies that investigate organo-mineral interactions up to the size of microaggregates in soil and sediments, including their time dependence, conceptual, analogic or numerical modeling, the spatial explicit characterization of organo-mineral associations down to the nanoscale through high-resolution imaging microscopies and spectroscopies, the impact of plant C input, the role of the soil fauna and microorganisms, as well as their potential to increase C storage in any types of ecosystem.

Note: This session is a merger of SSS5.6 "Organo-mineral association dynamics in soil" and SSS5.10 "Microaggregates in Soil"

The Amazon forest is the world’s largest intact forest landscape. Due to its large biodiversity, carbon storage capacity, and role in the hydrological cycle, it is an extraordinary interdisciplinary natural laboratory of global significance. In the Amazon rain forest biome, it is possible to study atmospheric composition and processes, biogeochemical cycling and energy fluxes at the geo-, bio-, atmosphere interface under near-pristine conditions for a part of the year, and under anthropogenic disturbance of varying intensity the rest of the year. Understanding its current functioning at process up to biome level in its pristine and degraded state is elemental for predicting its response upon changing climate and land use, and the impact this will have on local up to global scale.
This session aims at bringing together scientists who investigate the functioning of the Amazon and comparable forest landscapes across spatial and temporal scales by means of remote and in-situ observational, modelling, and theoretical studies. Particularly welcome are also presentations of novel, interdisciplinary approaches and techniques that bear the potential of paving the way for a paradigm shift.

Terrestrial ecosystems across the globe are being exposed to elevated atmospheric CO2, causing increase in temperatures and more frequent and intense drought and rainfall events. These changes have strong implications for biogeochemical cycling and the functioning of terrestrial ecosystems. Understanding the mechanisms controlling the response of plants and soil biota to climate change is therefore critical to predict potential feedbacks of terrestrial ecosystems to future climate scenarios.

The aim of this session is to bridge the knowledge of different disciplines to elucidate the multi-scale mechanisms and feedbacks underpinning the biogeochemical response to climate change, with emphasis on warming, drought and drying-rewetting dynamics. This session will give a broad overview of empirical and modelling studies across different scales, considering how climate change affects terrestrial biogeochemistry and the interactions between soil, microorganisms, plants and fauna. Attention will be given to the resistance or adaptation mechanisms of plants and soil biota during single or repeated environmental disturbances, as well as to the resilience and the associated temporal recovery dynamics after a disturbance. We will bring together researchers from different environments and create a discussion platform to review the current state-of-the-art, identify knowledge gaps, share ideas, and tackle new challenges in the field.

The changes in mineral and organo-mineral assemblages during pedogenesis are affected by chemical weathering and transformation of primary minerals over a wide range of time scales. The subsequent formation and transformation of secondary minerals are tightly linked to hydrological conditions and biological processes. Changes in mineral types, organo-mineral organisation and reactivities constrain the biogeochemical cycles of major elements (e.g., silicon, carbon, nitrogen, phosphorus, and sulphur) and trace elements (e.g., iron, manganese, antimony, cadmium, molybdenum, and selenium) which are often intricately coupled and controls the release, transport, and immobilization of nutrients and toxic trace elements, especially in redox-dynamic soil environments. The distribution of elements in soil affects soil quality, biota, ecosystem health, and ultimately, Earth’s climate and life. In this session, we invite field, laboratory, and modelling studies from a molecular-level to ecosystem observations exploring:
(1) the mechanisms and rates of mineral weathering, formation, and transformation at different time scales, as well as the links to biogeochemical element cycling,
(2) the speciation, reactivity, and environmental fate of elements during soil wetting and drying, freezing and thawing, and changing water-flow regimes, and
(3) the impact of mineral weathering and redox oscillations on element turnover, climate, and biota.

Organic substances in the soil are very heterogeneous and include low and high molecular weight compounds, and may be derived from plant and microbial residues. Besides contribution to soil organic matter (SOM) formation, living microorganisms regulate C and nutrient cycles by recycling processes. Detailed analyses of SOM transformation can highlight the role of selective preservation mechanisms, for example, and how these are modified and influenced by biological, physical and chemical interactions. In order to link processes of SOM formation with the pools, the broad range of approaches is used, including an application of various isotopes 13C/14C, 15N, 18O, 33P and analysis of plant and microbial biomarkers comprising both structural and chemical aspects related to SOM turnover. The specific attention is dedicated to the low molecular weight organic substances (LMWOS), which serve as a fuel for microorganisms, regulates their activity, composition, the transition from dormant to active stages and transformation of SOM (e.g. priming effect).
Thus, this session invites contributions, especially from early-career students, to i) the fate and turnover of organic substances in soil: from uptake and utilization by microorganisms to stabilization in SOM, ii) functions of LMWOS for priming of SOM decomposition, regulation of nutrient availability and rock weathering, iii) microbial recycling of elements (C, N, and P) from fresh or aged organic material. Analytical approaches comprising structural and chemical aspects related to SOM, such as potential biomarkers, isotopes, and their combinations are highly desirable. We also encourage contributors to present and discuss analytical challenges that remain due to both environmental and analytical uncertainty.

The coastal ocean has been increasingly recognized as a dynamic component of the global carbon budget. This session aims at fostering our understanding of the roles of coastal environments and of exchange processes, both natural or perturbed, along the terrestrial / coastal sea / open ocean continuum in global biogeochemical cycles. During the session recent advancements in the field of coastal and shelf biogeochemistry will be discussed. Contributions focusing on carbon and nutrient and all other element's cycles in coastal, shelf and shelf break environments, both pelagic and sedimentary, are invited.

This session is multidisciplinary and is open to observational, modelling and theoretical studies in order to promote the dialogue. The session will comprise subsections on coastal carbon storage, and on benthic biogeochemical processes.

This year the session comprises a subsection focusing on the Franco-German “Make Our Planet Great Again” (MOPGA) research initiative, which uses Earth system science to understand climate change and its impacts:
At the 2015 Paris COP21 climate conference, 195 countries committed to reduce their greenhouse gas emissions and make efforts to significantly limit man-made global warming to below 2°C above pre-industrial levels. France and Germany joined forces in this fight against global warming by creating the “Make Our Planet Great Again” research initiative covering research in Earth system science that aims to better understand climate change and its impacts on natural and socio-economic systems. In this interdisciplinary session, we welcome data- and model-based research undertaken within, but also outside this international initiative, that provides new insights into the mechanisms of past, present and future climate changes and the associated impacts on the oceans, the cryosphere, coastal regions, and terrestrial systems. Innovative research contributions that can lead towards the ultimate goals of the Paris Agreement ranging from basic research to solution-oriented research are also encouraged.

Permafrost thaw is expected to amplify the release of previously frozen material from terrestrial into aquatic systems: rivers, lakes, groundwater and oceans. Current projections include changes in precipitation patterns, active layer drainage and leaching, increased thermokarst lake formation, as well as increased coastal and river bank erosion that are further enhanced by rising water temperatures, river discharge and wave action. In addition, subsea permafrost that formed under terrestrial conditions but was later inundated might be rapidly thawing on Arctic Ocean shelves. These processes are expected to substantially alter the biogeochemical cycling of carbon but also of other elements in the permafrost area.
This session invites contributions on the mobilization of terrestrial matter to aquatic systems in the permafrost domain, as well as its transport, processing and potential interaction with autochthonous, aquatic matter. We encourage submissions focusing on organic and inorganic carbon as well as on other elements such as nitrogen, phosphorus, silica, iron, mercury and others, from all parts of the global permafrost area including mountain, inland, coastal and subsea permafrost, on all spatial scales, in the contemporary system but also in the past and future, based on field, laboratory and modelling work.

Public information:
The session will follow a loose sequence from permafrost soils to lakes, rivers, and the Arctic Ocean, closing with Arctic Ocean methane (see the list in session materials). Welcome!

Aquatic sediments are ecologically diverse and important environments, which shelter and support a variety of benthic animals and plants. Active reworking and ventilation by macrobenthic communities control the physical structure and biogeochemistry of sediment by redistribution of solids (e.g. organic carbon sources), solutes (e.g. oxygen), and microorganisms. Examples vary in scale and effect, including oxygen entrainment into riverbeds by nesting salmon, rapid bioirrigation of deep burrows by benthic invertebrates, large-scale sediment remodelling by tunnelling crustaceans (bioturbation), and oxidation of metals in the rhizosphere of macrophytes. Much of our knowledge on sediment biogeochemistry, hydrodynamics and geomicrobiology is derived from studies on undisturbed sediments, yet the majority of sediments are in some way affected by the macrobenthos. We therefore aim to gather novel research that links physico-chemical and microbial properties of the sediment to its (macro)biological community. This session invites contributions describing interactions between benthic fauna and the sediment, with emphasis on sediment biogeochemistry, hydrodynamics, geomicrobiology or molecular interactions. We aim to balance research that is field-, laboratory- and computational-focussed.

The last two decades have brought major technological advancements in characterisation of aquatic organic matter with spectroscopic and chromatographic methods and collection of water quality data at high spatial and temporal resolution with automated in situ instruments. The aim of this session is to demonstrate if and how this methodological advancement improves our understanding of dominant hydrochemical and ecological processes in aquatic environments controlling the fate of organic matter, nutrients and other pollutants.

Specifically, our ability to characterise different fractions of natural organic matter has increased thanks to a range of analytical methods e.g. fluorescence and absorbance spectroscopy, mass spectrometry and chromatography combined with new data mining tools (self-organising maps, PARAFAC analysis). Matching the water quality measurement interval with the timescales of hydrological responses (from minutes to hours) thanks to automated in situ wet-chemistry analysers, optical sensors and lab-on-a-chip instruments has led to discovery of new hydrochemical and biogeochemical patterns in aquatic environments e.g., concentration-discharge hysteresis and diurnal cycles. We need to understand further how hydrochemical and ecological processes control those patterns, how different biogeochemical cycles are linked in aquatic environments (e.g., carbon, phosphorus, nitrogen, sulphur and iron) and how human activities disturb those biogeochemical cycles by emitting excess amounts of nutrients to aquatic systems. In particular, there is a growing need to better characterise the origins, delivery pathways, transformations and environmental fate of organic matter and nutrients in aquatic environments along with identification of robust numerical tools for advanced data processing and modelling.

Previously in this session:
2019 https://meetingorganizer.copernicus.org/EGU2019/session/32089
2018 https://meetingorganizer.copernicus.org/EGU2018/session/26401
2017 http://meetingorganizer.copernicus.org/EGU2017/session/24958
2016 http://meetingorganizer.copernicus.org/EGU2016/session/20013
2015 http://meetingorganizer.copernicus.org/EGU2015/session/17101
2014 http://meetingorganizer.copernicus.org/EGU2014/session/15261

Due to the growing pressures on marine resources and the ecosystem services demand, the interest of scientific and politic world is moving to ensure marine ecosystems conservation and environmental sustainable development providing policies to meet the UN 2030 Agenda Goal 14 in order to “Conserve and sustainably use the oceans, seas and marine resources for sustainable development”. To act against the decline of the ocean health and to create a framework of stakeholders, the UN proposed the establishment of the “Decade of Ocean Science for Sustainable Development” able to bring regional knowledge and priorities together in an international action plan. Anthropogenic activities could have an impact on the marine environment and affect the ecosystem equilibrium. The marine environment is a dynamic, sensitive and fragile area in which it is advantageous to apply new methodologies and observing methods to increase the quantity and quality of the data. Since ocean dynamical affect the dispersion of pollutants such as chemicals, plastics, noise and invasive species, the ecosystems status should be analyzed through the study of abiotic variables distribution at a proper spatio-temporal scale. To analyze the ocean environmental quality, a large amount of data obtained by global observation systems (e.g. GOOS, EMODNET) is needed, which requires the development of cost-effective technologies for integrated observing systems and to support the study of, e.g., biological variables. The session focuses on marine ecosystems and biogeochemistry, technological developments for the study of abiotic and biotic factors, with a focus on anthropogenic impacts. Multidisciplinary approaches using data coming from multiple sources are encouraged. Integration of mathematical models, in-situ and remote observations is suggested with the aim to develop methods, technologies and best practices to maintain, restore and monitor biodiversity and to guarantee sustainable use of marine resources. The following topics will be discussed: effects of pollution on biota considering their natural and anthropogenic sources; short-term and long-term impact of economic activities on the seabed; potential remediation of diverse anthropogenic alterations on the seafloor; global change effects on marine ecosystem; new technology development; advanced methods for collection, data processing, and information extraction; benthic and pelagic community dynamics; economic evaluation of natural capital.

The rapid decline of Arctic sea ice in the last decade is a dramatic indicator of climate change. The Arctic sea ice cover is now thinner, weaker and drifts faster. The ocean is also changing; the volume of freshwater stored in the Arctic and has increased as have the inputs of coastal runoff from Siberia and Greenland. Concurrently inflows from the Atlantic and Pacific Oceans have warmed. As the global surface temperature rises, the Arctic Ocean is speculated to become seasonally ice-free in the 21st century, which prompts us to revisit our perceptions of the Arctic system as a whole. What could the Arctic look like in the future? How are the present changes in the Arctic going to affect the lower latitudes? What aspects of the changing Arctic should future observations, remote sensing and modelling programmes address? The scientific community is investing considerable effort in making the current knowledge of the physical and biogeochemical properties of the Arctic more systematic, in exploring poorly understood coupled atmosphere-sea-ice-ocean processes to improve prediction of future changes in the Arctic.

In this session, we invite contributions from a variety of studies addressing the recent past, present and future Arctic. We encourage submissions examining interactions between the ocean, atmosphere and sea ice and on studies linking changes in the Arctic to the global ocean. Submissions with a focus on emerging cryospheric, oceanic and biogeochemical processes and their implications are particularly welcome.

The session promotes results from current Arctic programmes and discussions on future plans for Arctic Ocean modelling and measurement strategies, and encourage submissions on the results from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC).

Decreasing sea-ice coverage, increasing permafrost-derived inputs and increasing ice sheet and glacier discharge will continue to affect high latitude environments in the coming decades under all future climate scenarios. Such changes at the interface between the ocean and the cryosphere raise questions about the downstream effects in marine ecosystems, as increased meltwater discharge is likely to impact not only coastal hydrology but also biogeochemistry, sediment transport and ecosystem services such as fisheries and carbon sequestration. However, the impact of increasing melt on fjord and coastal environments is poorly constrained, impacting our ability to make predictions regarding the consequences of future climate change. In order to understand the effect of changing cryosphere-derived inputs on high latitude fjords and marine coastal environments, knowledge concerning the physical and biochemical perturbations occurring in the sea ice and water column and the structure, function and resilience of affected ecosystems must be integrated. In this session we explicitly welcome cross-disciplinary attempts to understand how far reaching the effects of sea-ice, permafrost derived material and glacial changes are on marine biogeochemistry, productivity, biodiversity, and ecosystem services. Topics may include, yet are not limited to, the effect of sea-ice, permafrost, and glacier discharge on sea-ice and water column structure, primary and secondary production, community structure, macronutrient and micronutrient availability, microbial processes, the carbonate system, and the biological carbon pump. Modelling experiments, and studies based on long-term observational records including sediment traps and proxy reconstructions from marine sediment cores are also welcome.

In recent years the interaction between the ocean and the cryosphere in the marginal seas of the Southern Ocean has become a major focus in climate research. Questions such as "Why has Antarctic sea ice only recently begun to decline?", "What controls the inflow of warm water into ice shelf cavities and how does it interact with the ice?", and “What are the dominant processes in ice-ocean boundary layers?” have attracted scientific and public attention. Recent advances in observational technology, data coverage, and modeling provide scientists with a better understanding of the mechanisms involving ice-ocean interactions of various types in the far South. Processes on the Antarctic continental shelf have been identified as missing links between the cryosphere, the global atmosphere and the deep open ocean that need to be captured in large-scale and global model simulations. Similarly, our limited knowledge of processes in ice-ocean boundary layers, such as heat and salt fluxes that control the melt rate, has been identified as a limitation on our ability to fully understand, let alone parameterize melting and freezing at interfaces between the ocean and ice shelves, icebergs, glaciers, and sea ice.

This session includes studies of the Southern Ocean's marginal seas including the Antarctic continental shelf and ice shelf cavities, as well as process studies with a particular focus on ice-ocean boundary layers and on all scales, from the ice-ocean interface to local to basin-scale to circumpolar. Physical and biogeochemical interactions between ice shelves, sea ice and the open ocean will be presented, along with their impacts on the greater Antarctic climate system. Presentations include theoretical studies as well as those based on in-situ observations, remote sensing, and process-scale, regional and global models. While the primary focus of the session is on ice-ocean interactions, we also includes contributions on ice-covered freshwater lakes.

The Southern Ocean around the latitudes of the Antarctic Circumpolar Current is a key region for the vertical and lateral exchanges of heat, carbon and nutrients, with significant impacts on the climate system as a whole. The role of the Southern Ocean as a sink of anthropogenic carbon and heat, and as a source of natural carbon in present and future climate conditions remains uncertain. To reduce this uncertainty, understanding the physical and biogeochemical processes underlying the Southern Ocean internal variability and its response to external forcing is critical. Recent advances in observational capabilities, theoretical frameworks, and numerical models (e.g. CMIP6 simulations) are providing a deeper insight into the three-dimensional patterns of Southern Ocean change. This session will discuss the current state of knowledge and novel findings concerning the role of the Southern Ocean in past, present, and future climates. In particular, it will address physical, biological, and biogeochemical processes, including interior ocean mixing and transport pathways, the cycling of carbon and nutrients, as well as ocean-ice-atmosphere interactions, and their wider implications for lower latitudes and the global climate.

Highlight: Solicited speaker Michael Meredith will report on the outcomes of the Polar Regions chapter of the recent "IPCC Special Report on the Ocean and Cryosphere in a Changing Climate" during this session.

Ocean oxygen loss is one of the key consequences of climate change and has the potential to critically impact marine biogeochemical cycles and ecology. Current time series projections and climate models identify an unusually rapid decline in oxygen concentrations, particularly in tropical regions. However, our understanding of how stable this trend is over longer time scales, how adaptable ecosystems are, and if negative or positive feedback mechanisms exist is insufficient.

We seek to identify major gaps in knowledge helping to quantify the rate of ocean deoxygenation and its impact on both biogeochemistry and marine life. To do so, this session aims to bring together scientists from across disciplines including physical oceanography, climate modeling, biogeochemistry, and deep time experts. Our aim is not only to bring our results together but to conclude on what changes in ocean oxygen content can be identified across different ocean areas and different geological timescales.

We invite contributions that investigate ocean deoxygenation in the past, present and future ocean, and its physical, chemical and/or biological drivers, using observational or model-based approaches at regional or global scales.

Over the past decades, emission reductions for air pollution abatement resulted in changes in precipitation, cloud and aerosol chemical composition, and in atmospheric deposition of anthropogenically derived nutrients to the ocean, affecting atmospheric acidity and atmospheric deposition to ecosystems.
Atmospheric acidity is central to many processes in the atmosphere and the Earth system: atmospheric chemistry, biogeochemical cycles, atmospheric deposition, ecosystems, human health, and climate. Atmospheric deposition impacts on marine productivity, oceanic carbon dioxide uptake and emissions to the atmosphere of climate active species. These oceanic emissions of reactive species and greenhouse gases influence atmospheric chemistry and global climate, and induce potentially important chemistry-climate feedbacks. Thus, air-sea fluxes of biogeochemically active constituents have significant impacts on global biogeochemistry and climate.
Despite the wide range of important effects of atmospheric acidity and air-sea exchanges, scientific knowledge gaps remain. Understanding atmospheric acidity’s levels, its spatial and temporal variability and controlling factors in the precipitation and the suspended atmospheric media, aerosols and clouds, and its multiple impacts, is an open scientific topic for research. We also still lack understanding of many of the physical and biogeochemical processes linking atmospheric deposition, atmospheric acidity, nutrient availability, marine biological productivity, and the biogeochemical cycles governing air-sea fluxes of these climate active species. Atmospheric inputs of other toxic substances, e.g., lead, cadmium, copper, and persistent organic pollutants, into the ocean are also of concern.
To address these current knowledge gaps, in this session we welcome new findings from laboratory, in-situ and remote sensing observations and atmospheric and oceanic numerical models, on the status of atmospheric acidity, the factors that affect its levels, its wide range of impacts, on atmospheric deposition of nutrients and toxic substances to the ocean, their impacts on ocean biogeochemistry, on the air-sea fluxes of climate active species and potential feedbacks to climate.
This session is jointly sponsored by GESAMP Working Group 38 on ‘The Atmospheric Input of Chemicals to the Ocean’, the Surface Ocean-Lower Atmosphere Study (SOLAS), and the International Commission on Atmospheric Chemistry and Global Pollution (iCACGP).

The Indian Ocean is unique among the other tropical ocean basins due to the seasonal reversal of monsoon winds and concurrent ocean currents, lack of steady easterlies that result in a relatively deep thermocline along the equator, low-latitude connection to the neighboring Pacific and a lack of northward heat export due to the Asian continent. These characteristics shape the Indian Ocean’s air-sea interactions, as well as its variability on (intra)seasonal, interannual, and decadal timescales. They also make the basin and its surrounding regions, which are home to a third of the global population, particularly vulnerable to anthropogenic climate change: robust trends in heat transport and freshwater fluxes have been observed in recent decades in the Indian Ocean and Maritime Continent region. Advances have recently been made in our understanding of the Indian Ocean’s circulation, interactions with adjacent ocean basins, and its role in regional and global climate. Nonetheless, significant gaps remain in understanding, observing, modeling, and predicting Indian Ocean variability and change across a range of timescales.
This session invites contributions based on observations, modelling, theory, and palaeo proxy reconstructions in the Indian Ocean that focus on understanding recent observed and projected changes in Indian Ocean physical and biogeochemical properties and their impacts on ecological processes, links between Indian Ocean variability and monsoon systems on (intra)seasonal to interannual timescales, interactions and exchanges between the Indian Ocean and other ocean basins, natural decadal variability, and extreme events. Contributions are sought in particular that address research on the Indian Ocean grand challenges highlighted in the recent IndOOS Decadal Review, and as formulated by the Climate and Ocean: Variability, Predictability, and Change (CLIVAR), the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), and the International Indian Ocean Expedition 2 (IIOE-2) programs.

It has been shown that regional climate change interacts with many other man-made perturbations in both natural and anthropogenic coastal environments. Regional climate change is one of multiple drivers, which have a continuing impact on terrestrial, aquatic and socio-economic (resp. human) environments. These drivers interact with regional climate change in ways, which are not completely understood. Recent assessments all over the world have partly addressed this issue (e.g. Assessment of Climate Change for the Baltic Sea region, BACC (2008, 2015); North Sea Climate Change Assessment, NOSCCA (2011); Canada’s Changing Climate Report, CCCR (2019)).
This session invites contributions, which focus on the connections and interrelations between climate change and other drivers of environmental change, be it natural or human-induced, in different regional seas and coastal regions. Observation and modelling studies are welcome, which describe processes and interrelations with climate change in the atmosphere, in marine and freshwater ecosystems and biogeochemistry, coastal and terrestrial ecosystems as well as human systems. In particular, studies on socio-economic factors like aerosols, land cover, fisheries, agriculture and forestry, urban areas, coastal management, offshore energy, air quality and recreation, and their relation to climate change, are welcome.
The aim of this session is to provide an overview over the current state of knowledge of this complicated interplay of different factors, in different regional seas and coastal regions all over the world.

This session provides a platform for cross-disciplinary science that addresses the continuum of the river and its catchment to the coastal sea. We invite studies across geographical borders; from the source to the sea including groundwater, and across the freshwater-marine water transition. The session welcomes studies that link environmental and social science, address the impacts of climate change and extreme events, and of human activities on water and sediment quality and quantity, hydromorphology, biodiversity, ecosystem functioning and ecosystem services of River-Sea systems, and that provide solutions for sustainable management of the River-Sea social-ecological system.
We need to fully understand how River-Sea-Systems function. How are River-Sea-Systems changing due to human pressures? What is the impact of processes in the catchment on marine systems function, and vice versa? How can we discern between human-induced changes or those driven by natural processes from climate-induced variability and extreme events? What will the tipping points of socio-ecologic system states be and what will they look like? How can we better characterise river-sea systems from the latest generation Earth observation to citizen science based observatories. How can we predict short and long term changes in River-Sea-Systems to manage them sustainably? What is the limit to which it is possible to predict the natural and human-influenced evolution of River-Sea-Systems? The increasing demand to jointly enable intensive human use and environmental protection in river-sea systems requires holistic and integrative research approaches with the ultimate goal of enhanced system understanding.